One-Hour Wargames Marengo - Part 3: Combat

With scale issues and movement rules dealt with, it’s now time to discuss my amendments to those OHW’s rules bits and pieces dealing with actual fighting, i.e. how to best model thousands of muskets, rifles, cannons, howitzers, bayonets and sabres inflicting casualties, spreading terror and generally doing nasty stuff to the enemy.

I find this the weakest part of OHW’s rules-as-written (RAW) from the viewpoint of historical realism, since there’s a distinct lack of modelling wrt many of the peculiar troop interactions which gave Napoleonic battles their specific flavour. My goal with these amendments is to put in the ruleset as many ‘true-to-period’ tactical choices as possible, without using anything else than OHW’s basic framework; that is, a given unit will inflict ‘X’ hits on the opponent in a given situation, and that’s it. Is it a delusional goal? I think it’s not, but I’m biased. Here’s what I’ve come up with:

(1)       Slight change to Turn Order: Shoot first, ask later

In OHW’s RAW, shooting occurs after movement – but units cannot both shoot and move. This means that on any single given turn, you cannot ‘soften up’ an enemy position before committing to an assault, since your charging unit/s will most probably obscure LOS to the intended target. This is very frustrating. Since OHW makes things quite difficult for the attacker already, I’ve simply switched the order to allow a modicum of coordination between supporting and assaulting units.

(2)       Don’t mess with the Cuirassiers: no amendments to Heavy Cavalry

In the RAW, cavalry units clearly represent squadrons of shock cavalry. They possess the strongest attack in the RAW, and a flank charge by them is as decisive as it should be. All in all I think they’re mostly fine, if perhaps a tad too strong in frontal/unsupported charges for my tastes… but I’ve decided this might be more due to a lack of close range firepower from musketry and artillery rather than anything wrong in the cavalry rules per se. So I still play shock cavalry exactly as in the RAW.

Now - one might be of course eager to model all other kinds of cavalry in Napoleonic engagements (and I confess I already have rules for Hussars and Dragoons in my games), but OHW’s ethos is to just outline the quintessence, so let’s leave all this to future posts.

In OHW terms, this means (I’ve included a quick recap of each unit’s special movement rules, which were discussed in the previous post, for convenience):

Unit name: ‘Cavalry’

Troops represented: around 750 men in several squadrons covering a 250m (6”) frontage; I use an exaggerated base depth of 50m to model the space occupied by straying/second wave squadrons.

Most probable formation: double line at the front; not all effectives are in the front ranks when at full strength.

Movement allowance: 12” (500m) per turn.

Special Movement rules: Can interpenetrate light infantry at any angle, and stationary artillery with the same facing. Cannot enter woods. Damaged (1d6-2) upon moving through mud/marsh.

Attacks:

-           Strong (1d6+2) close combat attack. Needs LOS to charge in.

-           Inflict double hits on targets charged on flank/rear.

Special Defences:

-           Repulsed 6” maintaining facing if target not dispersed.

(3)       Making Smoothbore Artillery less Smoothboring

In the RAW, artillery is quite boring. They always inflict the same number of hits regardless of range and/or positioning. Due to this, some of the typical historical behaviors of troops facing artillery batteries just don’t occur. I’ve chosen three key aspects of Napoleonic era batteries I wanted to model in my games:

(1) close range canister fire should be scary,

(2) bombardment should cause more damage to squares and en enfilade than defilade fire, and

(3) cannonball range should be somewhat dependent on the ground’s condition.

Quantitative hard-and-fast assumptions include:

- Effective cannonball range is assumed to be 1000m, increased to 1500m on good terrain due to bounce

- Long range artillery bombardments are unsustainable in the long term but not quickly decisive

- Effective canister range is assumed to be 250m

Unit name: ‘Artillery’

Troops represented: One or two field batteries plus accompanying infantry escort, distributed on a 250m (6”) frontage; the overall depth of a battery including caissons is around 150-200m! My blocks are 150m deep (I mean at scale, just in case anyone is wondering).

Most probable formation: Individual pieces spaced by around 15m laterally; accompanying infantry interspersed in both width and depth.

Movement allowance: 6” (250m) per turn. Can’t fire if moved, implicitly modelling limbering/unlimbering.

Special Movement rules: Cannot use fords, cannot enter muddy ground or marshes, cannot enter woods, cannot shoot out of a BUA. Can interpenetrate light infantry at any angle.

Attacks:

-           Bombardment: weak (1d6-2) ranged attack up to 24” (1000m), range increased to 36” (1500m) if the entirety of the firing path above 12" doesn't include rivers, lakes, muddy or marsh areas (inhibiting cannonball bounce).

-           Canister: medium (1d6) ranged attack up to 6” (250m).

-           Enfilade fire: inflict double hits if firing into the flanks of line infantry and cavalry (only).

Special Defences: none.

Design Notes: the enfilade fire bonus makes obtaining/avoiding flanking important, and brings new life to a few of OHW’s scenarios in which being flanked should be an issue – but it isn’t much. Improved canister effectiveness makes frontal engagement somewhat more risky (especially by cavalry, which will be still in range after a repulsed charge).

(4)    Poor Bloody Infantry

Line infantry is very appropriately the most common unit in OHW’s random H&M‑era army list generator, but it feels a bit ‘flat’ when played by the book. Their 12” shooting range represent my biggest gripe with the RAW: if 12” represents musketry range, then 6”-wide infantry units can only be individual battalions at most. This makes standard six-units games très petite, and the abstraction of tactical formations highly questionable. Instead, I think OHW’s very abstract mechanics are best suited to higher scales, so I decided that standard infantry units should represent regiments, demi-brigades or understrength (that is, most) brigades, with other units scaled accordingly. But this meant that all attack ranges had to completely be re-thought. By doing this, I took the opportunity to introduce a few more tactical choices for infantry, in particular about battle tempo/intensity of effort… More choices mean more possible errors and more interesting games, at least I hope.

Hard-and-fast assumptions include:

-           Effective massed musketry range is 125m

-           Massed musketry is scary at close range

-           Sharpshooting/sniping has a slightly longer effective range due to better equipment/training

-           All line infantry units have an ‘implicit’ screen of skirmishers around 250m forward of their front

-           Due to their forward positioning and their longer range, skirmishers can start low-intensity engagements 500m forward of the parent infantry unit.

-           All line infantry units have a few integral battalion guns whose effective range is 500m

-           Initiating a determined bayonet charge can dislodge shaky enemy infantry regardless of whether actual hth fighting occurs

-           Given enough space and time, infantry could form square to protect themselves quite effectively from isolated cavalry charges

-           Massed infantry was very susceptible to artillery when in squares or when receiving enfilade fire

All of which can be translated surprisingly easily into OHW’s jargon:

Unit name: ‘Infantry’

Troops represented: Around 2000 close order muskets on a 250m (6”) frontage. Again, I use a depth of 50m to represent the space occupied by supporting battalions and/or column depth.

Most probable formation: Continuous front line of 2-3 ranks, often with supporting battalions at the back; or ordre mixte; or attack columns, in all cases with interspersed space to maneuver effectively.

Movement allowance: 6” (250m) per turn. Can’t fire if moved, implicitly representing the adoption of formations optimized for movement or combat. The only type of formation explicitly represented under my amendments is the column of route (see previous post).

Special Movement rules: Can interpenetrate light infantry at any angle, and stationary artillery with the same facing. Cannot enter woods.

Attacks:

-           Massed Musketry: strong (1d6+2) attack with a range of 3” (125m)

-           Long-range, low-intensity engagement via skirmishers and battalion guns: weak (1d6-2) attack at a range of 12” (500m).

-           Bayonet charge: when an enemy unit is destroyed via massed musketry, optionally move the firing unit up to 3” to the previous position of their (now defunct) target, simulating the last decisive assault.

Special Defences:

-           Form Square: when charged by one or more cavalry units, optionally change facing immediately before contact.

Design Notes: Shooting ranges are now more realistic. Having two types of attack makes it possible to differentiate between low- and high-intensity engagements, enabling the commander to choose local battle tempo. Moreover, in infantry vs infantry engagements there is now an option to shoot at long range then retreating before an opponent who wants to close in to musketry range, thus making fighting withdrawals a possibility. Bayonet charges are only implied but allow to capture terrain more quickly than in the RAW. The free turn toward a charging cavalry unit abstractly represents the adoption square formations: it will considerably protect the musketeers but also make them more vulnerable to artillery previously shooting on its front due to the new enfilade bonus.

(5)    The unbearable lightness of light infantry

I find ‘skirmishers’ are the most problematic unit type playing them by the book. First of all, what do they represent exactly in the RAW? It’s not clear, but – given that infantry units are probably battalions - probably sub-battalion-sized, ad-hoc formations of voltigeurs, chasseurs and the like. In the RAW, they move faster than line infantry and can enter dense terrain (i.e. woods). The rules say they represent half the manpower of a line infantry, but can soak the same number of hits- thus modeling the protection afforded by their dispersed formation in a very Kriegsspiel-like fashion. However, I’ve found that unit-for-unit, RAW-skirmishers are the weakest troops, and often a liability rather than an asset. Their niche seems to be to enter woods and just stay there without accomplishing much… More often than not, the best plan when facing skirmishers is just ignoring them; they won’t be much of a factor in the end.

However! Historically, light infantry was much more than this: it was the prime choice for urban/BUA fighting, it was decidedly annoying to formed infantry at range (forcing them to either withdraw or close the range), it was a good counter for artillery, etc etc. Moreover, skirmishers should be much more vulnerable to cavalry than to massed musketry and artillery (while in the RAW, they can absorb a cavalry charge just as well as a massed infantry unit). It’s time to change all this!

To begin with, I’ll rename ‘skirmishers’ to ‘light infantry’, which is a bit more generic. These units might (rarely) represent ad-hoc light brigades, but a lot more often these will be infantry formations which, for a variety of reasons, have an unusually high proportion of skirmishers and/or a higher propensity than usual to approach the enemy in open order. Accordingly, this includes Voltigeurs, Legeres, Jagers, Chasseurs, Grenzers, Rifles, etc… but also standard line infantry formations ordered to massively reinforce a skirmishing line locally. Open order is not assumed for ALL troopers in the unit, but rather just by those actually engaging the enemy.

Here are the hard-and-fast assumptions I wanted to model in the rules:

-           As discussed for line infantry above, skirmishers can engage enemy formations at around 500m (12”) forward of the unit’s “centre of mass”.

-           Open order limits casualties from massed musketry and artillery bombardments, but is very vulnerable to cavalry charges, and does not particularly protect against sharpshooting.

-           Open order troops should naturally avoid proximity with massed enemies.

-           Sharphooters are very annoying to enemy artillery.

-           Sharpshooters are individually more effective than massed musketry to enemy in cover.

-           Except for a glorious cavalry charge in good terrain, the best counter to enemy skirmishers is having more skirmishers.

-           The battle tempo of skirmishing is a lot slower than that of massed infantry/cavalry engagements (Clausewitz would say it “burns slowly as wet powder”).

-           When faced with skirmishers, massed infantry can either accept slow attrition at long range, or close in to decisively disperse them.

An here is the same in OHW terms:

Unit name: ‘Light Infantry’

Troops represented: Around 1000 open order sharphooters on a 250m (6”) frontage. I use a depth of 50m (mostly representing empty space).

Most probable formation: Dispersed swarms of sharphooters, with individuals or teams of 2 men spaced by approximately 5-8m, each making most use of cover and shooting after careful aiming. If present, parent line infantry battalions are assumed to be at the back.

Movement allowance: 9” (250m) per turn.

Special Movement rules: Can enter woods. Can interpenetrate any unit at any angle.

Attacks:

-           Sharpshooting: weak (1d6-2) attack with a 12” range.

-           Accurate: sharpshooting hits are never halved due to cover (woods/BUAs/river banks).

Special Defences:

-           Open formation: light infantry only take half hits from attacks by line infantry and artillery; however, they take double hits when attacked by cavalry.

-           Disordered: light infantry units have no flanks; as such, cavalry cannot claim flank/rear charge bonuses (but hey, they still have the intrinsic x2 hits mentioned in the previous point).

Optional rule:

-           Reinforcing skirmishers/Closing ranks: “Skirmishing” was more often than not a task assigned to units rather than a designation for ad-hoc units. According to this, you can always transform a line infantry unit into a light infantry unit, and vice versa. This can be done at deployment, or during a normal turn (counting as the unit’s movement). In either case, the freshly transformed unit immediately takes 1d6-2 hits due to confusion and reorganization, so use this sparingly. Elite light units like ‘l’incomparable’ 9^th light or 95^th rifles can switch between light and massed behaviour without taking hits.

Design Notes: I felt skirmishers were the most useless unit as per the RAW. Sure, they could occupy woods, but once there they couldn’t achieve much. I’ve boosted their performance considerably to bring them in line with other units. I feel they better represent ‘elite’ formations now, especially if you use the optional light/line morphing rule (I do, it’s fun).

Light infantry units can engage massed infantry at long range at an advantage (although not decisively so), but are disadvantaged if they get too close. In both cases, they slow the battle tempo with respect to massed infantry engagements, buying you time to decide when and where to commit your heavies. Massed infantry can force skirmishers to relocate by closing the gap to them. A clever trick by the skirmishers would be to retire through (interpenetrating) a formed line in the rear when threatened, leaving the advancing enemy infantry exposed to friendly musketry. The fact that their attack is never halved by cover makes light infantry units prime choices for urban assaults, as they were historically. They also are a good response to enemy skirmishers!

Ludography:

Vive l'Empereur!
De Bellis Napoleonicis
Horse and Musket: The Dawn of an Era
Warfare in the Age of Reason
Two flags, one nation

Bibliography:

G. Nafziger is THE man.

Images:

Random web sources. I’ll take them down if it’s some form of infringement.

Web-o-graphy:

https://www.napoleon-series.org/

https://rodwargaming.wordpress.com/miltary-historical-research/organisation/napoleonic-infantry-battalion-structures/

https://rodwargaming.wordpress.com/miltary-historical-research/military-historical-research/basic-formations-and-movement-drills/

Napoleon : napoleonic wars : battles : armies : tactics : maps : uniforms (napolun.com)

One-Hour Wargames Marengo - Part 2: Terrain and Movement

Side note: despite having finalized these rules months ago - and routinely playing them – my progress on such things as diagrams and ‘proper’ draft writing occurs at a glacier’s pace. I always find more satisfying to actually play a wargame rather than writing about it; I’m afraid I’m not much of a blogger. Anyway, I’ll keep putting my finalized designs here for future reference.

In the previous post, I have broadly outlined the size of both the playing map and the playing pieces of my OHW Marengo scenario. It’s time to find how to make those blocks move around the battlefield in a way which makes (at least some) historical sense!

Starting from the map (again)

The first thing I did was to survey the square section of the historical map I decided to use for my OHW scenario and take notes about which types of terrain I needed to model the overall course of the battle:

Map 1: OHW-style square battlefield.

As I mentioned in the previous post, some of the features are a bit puzzling, so I’ve referred to a later map (approximately from the 1870s) to understand e.g. what exactly happens to the southern portion of the Fontanone. Unfortunately, this wasn’t very successful as the landscape seemed to change quite a lot during those 70-ish years, with the Fontanone being replaced by two different streams called Rio Boggio and Rio Ressia… In fact, I suspect that “Fontanone” (big fountain/canal) might just be a funny name for any small water course in the local dialect, just as “montagnone” (big mountain) might ironically denote any ditch higher than 10m. At least, the later map was useful in making me understand that all those straight lines in the SW corner of the map aren’t most probably roads, but irrigation ditches.

Map 2: Istituto Geografico Militare Survey Map (apparently from the 1870’s?)

It became immediately apparent that I needed a lot more terrain types w.r.t. OHW’s RAW. Based on the previous two maps, I’ve outlined these terrain types on the map itself:

Map 3 – Terrain types:

Blue – Watercourses (thick: major, thin: minor)
Dark Green – Woods
Light Green – Marsh/Muddy
Yellow – Ploughed Fields
Yellow with Green outline – “Alberata e Seminativo” fields (more on that below)
Red – Conurbations & smaller Built-Up-Areas, e.g. walled farms
Contour lines (uncolored) – Hills
Dots (uncolored) – Orchards
Most remaining lines – Road network (paved, dirt, or tree-lined avenues)

Just looking at the annotated map makes some aspects of the battle much clearer. For example, Marengo was just one of the many BUAs in the area, but it had the only solid bridge in the whole area across an almost uninterrupted series of creeks and marshes. Austrian artillery and cavalry just needed to clear that chokepoint – no wonder it became the crux of the battle. If you just treat anything east of the Bormida as clear terrain (as some rulesets do) then the historical Austrian course of action make no sense at all. In fact, Austrian troops emerging from the bridgehead just had four broad choiches:

(1) press forward along the road through Pietrabuona and Marengo: obvious choice but one with several drawbacks (COA historically followed by e.g. Kaim’s and Morzin’s troops)
(2) take the road to Castelceriolo: potentially decisive but very slow (COA historically followed by Ott, Schellenberg, Vogelsang etc)
(3) try to cross the Fontanone near La Barbotta (attempted e.g. by Elsnitz and Frimont)
(4) try to follow the eastern bank of the Bormida then cross the Fontanone at the ford (no ‘solid’ bridge there!) near La Stortigliona (disastrously attempted by O’Reilly)

…anything else seems highly unlikely. This means that all the advantage in cavalry and artillery by the Austrians is severely hampered by the terrain and that the French can concentrate their defense on a few well-chosen chokepoints. Moreover, the mere size of the Austrian army implies that they cannot choose the same COA for all troops: there’s just no space to do that. They need to split their force across the four possible approaches.

So far so good! But I needed to actually translate all of the above into OHW rules. This is what I’ve done:

Amendments to movement rules

First of all, I didn’t change OHW’s RAW movement rates, because they don’t seem too different to what everyone else is doing in other rulesets. Movement rates are quite tricky because they’re unavoidably intertwined with the modeled timescale: how far a formed infantry battalion can march in a turn depends on how much time a turn represents, of course. Moreover, even if I rigidly defined the length of a turn, I could only compute movement distances for formations moving in straight lines for the whole time – thus not taking into account formation changes, pauses, bursts of hyperactivity in response to enemy actions, etc etc.

OHW movement rates just imply that cavalry can on average move twice as fast as formed infantry, and I’m content with that for two reasons. First, it’s one of the parameters that Mr. Thomas took into account when fine-tuning OHW’s scenarios, so messing with that would impair the compatibility of my amendments with the scenarios as written – something I’d like to avoid. Second, I’ll be able to retroactively make movement rates as ‘realistic’ as possible by varying turn length and finding which one produces the most historical results. For this reason, I’ll leave the exact duration of one turn undefined for the moment. All in all, the movement allowances I’m using are the following:

Formation	Movement allowance per turn
Line Infantry	6” (250 m)
Skirmishing infantry	9” (375 m)
Heavy Cavalry	12” (500 m)
Artillery Battery (limbered)	6” (250 m)
Artillery Battery (unlimbered)	0” (0 m)

 …and here are some of the revised shooting ranges for comparison, but I’ll talk about those in a future installment (spoiler alert!):

Shooting Unit	Effective range
Musketry	3” (125 m)
Artillery (direct)	24” (1000 m)
Artillery (bounce)	36” (1500 m)

 While movement rates are more or less the same as in the Rules-As-Written (RAW), I use the following amendments to how movement is actually performed:

Interpenetration

Line infantry and cavalry can pass through artillery if they face the same direction as artillery AND artillery doesn't move this turn. Skirmishers can pass and be passed through anyone, at any angle (as per the RAW).

Columns of route (road movement bonus)

Road movement bonus is 6” (instead of 3” as in the RAW) for all units. However, to qualify for the bonus units must spend their entire move (including the extra 6”) on the road network, and they must pivot in a specific way at the end of the move, simulating the adoption of a non-combat formation: they must end their move with both of their flanks touching the road (see Figure 1), i.e. as if moving ‘sideways’ so to speak. Of course, only one unit can occupy a given length of road at the same time. Following this rule, units in column of route can get a substantial movement bonus but will arrive at their destination in a suboptimal combat formation (since they’ll need one further turn to attack anything in the general direction of their movement, or to avoid flank charges/enfilade extra hits).

Figure 1 – Columns of route and road movement. Left: The cavalry unit (below) has a normal movement allowance of 12”, so it can just move this far without restrictions (orchards and ‘normal’ fields are clear terrain, see below). The three infantry regiments only move 6”, but they decide to use the extra +6” road movement bonus to keep up with cavalry. To qualify for road movement bonus they must end their move with both flanks on the road; if they do so, their centre point can move 12”. Right: position after moving. The cavalry squadrons could move 12” without pivoting and are ready to charge any enemy appearing on their West; the three infantry regiments are instead in column of route, stretched out to around 750m along the road and not in a position to immediately project maximum offensive or defensive potential to the west.

Cavalry charges

Cavalry must have LOS to their target at the start of their move. Due to this, charges cannot be performed e.g. when interpenetrating an intervening friendly unit, or towards unseen enemies beyond a ridge. Cavalry can still charge when negotiating a bottleneck and/or when receiving a road movement bonus; in this case however they end their charge ‘sideways’, with their short flanks contacting the opponent (again, simulating suboptimal combat formations). Such hasty/constrained attacks only inflict 50% hits on the target.

Figure 2 – Cavalry charges. Left: both Futak 1° and Futak 4° dragoons are 18” away (I always measure distances via front centre points) from enemy formed infantry. Right: Futak 4° decides to use their standard 12” movement allowance to get closer to Chambarlhac’s men with all squadrons in line. Instead, Futak 1° are on a road and decide to stretch out into a hasty charge adding a +6” bonus to their 12” move. They can charge Chambarlhac 24°, but squadrons reach the enemy lines in a more piecemeal fashion: under my amendments, this is abstractly represented by putting the block ‘sideways’. This hasted charge will inflict half the usual amount of hits.

Rivers, Creeks and Streams

Major rivers such as the Bormida are impassable and can only be traversed at a ford or fixed/pontoon bridge (see below). Lesser but relevant water courses  such as the Fontanone creek can be crossed by infantry (both line and light) at any position, but crossing is hindered (i.e. must happen ‘sideways’, see below). Lesser water courses are impassable to artillery and cavalry; but while cavalry can still cross these at fords, artillery needs ‘real’ solid bridges such the one at the Marengo fortified farm. Infantry units (both line and light flavours) can cross lesser water courses at any point. Infantry units in contact with rivers of all types receive cover from attacks coming from the opposite bank (both shooting and charges – provided the latter are possible of course).

Bridges, fords, pontoons, bottlenecks and traffic jams

All units can only move across major bridges as part of a road move (see Figure 3a). Units crossing at fords and pontoon/minor bridges must in addition end their moves with their central point *on* the bridge/ford (Figure 3b - in practice, only one unit will be able to cross per turn). If the crossing point is not connected to a road then the crossing unit must also end with both its flanks on a line perpendicular to the edge of the just-negotiated obstacle (Figure 3c).

Figure 3 – Crossing at fords, bridges, etc. (a) Major bridge crossing. The Bormida is impassable along its whole course to all troops; the tête-de-pont at Alessandria is across a major bridge. All units must cross the bridge by normal road movement (see Fig. 1 above). (b) Road movement with no bridge. Elsnitz 3° Dragoons start their move on a road, so they could gallop up to 12+6=18” if they remained in column of route. However, they reach a ford much sooner. They must thus stop with their centre point on the ford, still in column. (c) Creek crossing with no road or bridge. Minor streams/creeks can be traversed at any point along their course by infantry, but units must stop with their centre point on the obstacle and forming column of route ‘as if’ on a perpendicular road.

Major conurbations (“Towns”) and smaller Built-Up-Areas (BUAs)

All unit types can occupy (i.e. end their move inside) towns; but only infantry can occupy BUAs. Units in towns and BUAs count all their sides as “front”; they can thus shoot 360° and cannot be charged/shot “in the flank/rear”. In addition to this, line and light infantry only receive 50% hits when attacked. Artillery cannot fire while in a town. Cavalry can only charge units inside towns and BUAs as if it was using road movement (regardless of whether they’re actually on a road or not at the start of their move); that is, they must charge “sideways” (inflicting 50% hits, see above).

Marshes / muddy ground

Artillery cannot enter these at all, and their cannonballs won’t “bounce” (details in the next instalment). Cavalry can move through it by suffering a weak (1d6-2) attack each turn due to the resulting chaos.

Alberata e Seminativo

Old‑fashioned vineyards as very, very probably in use near Marengo at that time (see also this excellent post). My late father used to work for the Italian ministry of agriculture, and I remember him telling me how modern/mechanized techniques really changed the way people used to grow vines. I remember how he explicitly talked about ‘alberata e seminativo’ (which is a modern agronomy name for an ancient practice) as an example. In old times (but in some remote places or in small family farms, probably up to the first half of XX century), vines were not usually assigned their own piece of turf, but were grown on fruit trees planted in straight rows around ploughed fields. Irrigation ditches were dug between adjoining fields. In a way, you can think of ‘alberata e seminativo’ vineyards as a (less extreme) version of bocage.

So my proposal for representing them at Marengo is to make them impassable to both artillery and cavalry. I know this sounds harsh, but I think it really makes sense when considering the historical course of the battle, and specifically the very limited impact all those Austrian cavalrymen made even after negotiating the main chokepoints.

Woods and hills

As per the RAW.

Ploughed fields and orchards

I’m inclined to treat these as clear terrain for no particular reason other than the battlefield seems already quite constrained as it is now. I’ll change this later if needed…

Design Notes

The only ‘exotic’ mechanism introduced in these amendment is the funky ‘sideways’ movement used to represent non-combat formations. I didn’t want to introduce any new marker/status/etc in addition to the hit track already used by OHW, and I think this works in a very abstract way. Basically, both columns of route and disordered/constrained formations are represented by turning the unit sideways with respect to the direction traveled. It’s a bit difficult to get tournament-tight wording on this, but I hope the schemes above convey the basic idea. I think it’s also a very simple way to model road traffic jams and units stretching out when in road column. Combined with the new artillery rules (see next post!) and cavalry charges, this also models the vulnerability of these formations to shot, as well their less-than-ideal combat efficacy, for almost no extra rules overhead.

Some of the various terrain-related amendments will probably have marginal impact at Marengo, but I feel they make sense. For example, defending/attacking towns and chateaux with dragoons and the like becomes possible, although far from ideal; this might perhaps come into play around Castelceriolo.

On the other hand, I feel some of the terrain amendments are crucial to really bring the Marengo map to life for OHW play. The most prominent example of this is probably that now ‘real’ bridges become more important than temporary/non-obvious crossing points (making that Marengo bridge all-important) and that creeks can be important defensive features (thus making defending the Fontanone a viable strategy).

In the next post, I’ll detail the combat-related amendments. In the meanwhile, take all of the above strictly just as my 2 pennies – pardon, Marengos…

 

One-Hour Wargames Marengo - Part 1: Scale

 

Lately, I’ve been reading a lot about the battle of Marengo. It’s a fascinating, if baffling, subject: several crucial aspects of the battle are very different in all reports I’ve found, including first-hand accounts. On top of that, when reading primary sources, one has to wade through several layers of self-aggrandizing revisionism by First Consul Bonaparte, complacent revisionism by his clients, and scornful revisionism by officers who deemed their achievements deserved greater rewards.

After deciding (somewhat arbitrarily, of course) which sources are most reliable, it’s possible to start putting all the pieces together. And the truth slowly emerges: what goes under the moniker “Battle of Marengo” is in fact a long, tragicomic series of SNAFUs and blunders by both sides over the course of at least two days.

In his fantastic blog “Obscure Battles”, Mr. Jeff Berry provides a very colourful and eminently enjoyable AAR:
Obscure Battles: Marengo 1800

The online magazine “War Times Journal” has a very nice page on Marengo which includes several primary documents:
The Battle of Marengo (wtj.com)

There are of course countless more reports and webpages devoted to Marengo, I’ll just link a few more among those most useful to wargamers here:
Battle of Marengo (frenchempire.net)
Jean Lannes » Marengo
Journal de voyage du Général Desaix, Suisse et Italie (1797) : Louis Charles Antoine Desaix de Veygoux , Louis-Charles-Antoine Desaix, Arthur Maxime Chuquet, Arthur Chuquet , Arthur Maxime, 1853 -1925 Chuquet : Free Download, Borrow, and Streaming : Internet Archive

Speaking of wargames, there are several published wargames on Marengo; my favourite ones are those (the fact that both use blocks is probably not a coincidence):
Battle of Marengo | Command Post Games
Bonaparte at Marengo | Board Game | BoardGameGeek

…but reading primary sources left me with a desire to experiment further with alternate course of actions and “what-ifs”. The simplest thing would probably be to modify Pub Battles’ Marengo official scenario and terrain rules to make both closer to primary sources. However, I’m a total rule nerd and I really enjoy designing simple wargames, so I started to reconsider everything from scratch instead. My vague design attempts quickly took a very specific direction: I wanted to jot down the simplest, fastest possible set of rules which would still give a broad picture of the tactical situation and Marengo. A logical place to start was thus the (arguably) simplest wargame I ever played: Neil Thomas’ One-Hour Wargames.

One‑Hour Wargames Marengo?

Is it at all reasonable to expect OHW to be able to model a ‘real’ battle like Marengo? Well, let me start with a categorical syllogism.

Major premise: Neil Thomas’ One-Hour Wargames, rules-as-written (RAW), give simple - but fun - Horse & Musket games focusing on small tactical exercises (scenarios) involving a handful of units. There’s a surprising tactical depth to be found in play, and the overall narrative is strikingly similar to what more ‘serious’ rulesets model given the same situation.

Minor premise: Realistic battlefield situations/historical scenarios can be regarded as the sum of many simultaneous, smaller tactical exercises similar to OHW’s scenarios.

Conclusion: It should be possible to play historical scenarios/full battles with OHW.

…however, after trying to condense the Marengo situation into a typical OHW scenario, I’ve found the result was so bland and generic as to feel utterly disconnected from the original historical event. There’s a number of problems involved in using historical OOBs with the RAW; so I wrote a set of amendments, which I’m currently playtesting with an ad-hoc created Marengo scenario. They seem to work! In this series of posts, I’ll dissect what I amended, how and why. At the end of the series, I’ll compile all the amended rules into a coherent (I hope) document.

Let’s start!

Step 1: Start with a great map.

Given my Kriegsspiel-inspired, map-and-blocks obsession, Marengo is a great choice: there’s a wonderful historical map available on the web – one of the very rare ones which doesn’t show troop positions and can be thus played upon without any kind of image processing. It’s the same map Command Post Games used as the basis for their Marengo game, and you can consult a copy at Simmons Games [edited to add - unfortunately their website seems to be down since a few weeks, I hope everything is fine]:

The map is wonderful, but it has a few quirks if you study it carefully enough.

For example, most people first playing Command Post Games’ Marengo are driven mad by the fact that there seems to be a major alley on both sides of the Bormida between Cascina Bianca and La Moglia – but apparently, no bridge or ford. Conversely, there seems to be some sort of crossing marked out near Montecastello across the Tanaro – but there’s no mention of such in historical accounts, and it would definitely be a bizarre omission given that it would definitely have mattered.

Moreover, the vexed question about the (alleged?) other bridge used by Ott’s division gets no clear answer on this map. Austrians infamously had a pontoon bridge established on June 13^th somewhere downstream (North) of Alessandria, and First Consul Bonaparte assigned Colonel Lauriston with the task to destroy it. Later that evening however, the officer admittedly reported to him that the order proved impossible to fulfil due to staunch Austrian resistance. The problem is, Napoleon later would claim he wasn’t informed about this by anyone, and assumed the bridge was positively destroyed when formulating the plan on the next day – this could explain his famous, subsequent judgement blunder…

Except it doesn’t. Reports are vague and discordant, but if the pontoon bridge was still there on June 14^th, then it didn’t play a large part in the battle. And it would be strange for it to be still there, given that it took Ott’s wing so long to cross the Bormida. In fact, there’s a direct mention of the pontoon bridge being unanchored and floated next to the permanent bridge at Alessandria in one of the sources… which also seems strange, given that Austrians would have needed to drag it against the river’s flow. Or is the mysterious dashed line at Montecastello the pontoon’s final position on June 14^th? Nobody knows, apparently. As with everything regarding Marengo, all of the above is just an educated guess. Some of the reports contain the same overall narrative regarding – not this extra pontoon bridge – but the main bridgehead in front of Alessandria. We’ll never know who’s right, I’m afraid.

It’s easy to criticize Bonaparte for his initial battleplan at Marengo (or rather, the absence of one). But, as it often happens throughout history, most great military commanders’ plans which hindsight exposed as ‘bad’ did in fact make perfect sense at the time of their formulation (including Cannae, but I’ll leave that one for another time). In this case, just imagine French commanders trying to drive Austrians off Marengo, late afternoon June 13^th. Then suddenly Austrians evacuate the fortified farm and retreat – not to their tete-de-ponte, but all the way into Alessandria, across the river. French troopers only stopped pursuing the retreating Austrians when coming into the sights of no less than two full artillery batteries, finally taking positions in the Pedrabona/Pietra Buona farm.

French high command reasoned that the only rational explanation for the Austrians’ course of action was that they had received orders to relocate somewhere else… but in fact, it was a C&C blunder: they were ordered to hold the tete-de-ponte at all costs on June 13^th evening! This proved to be a (totally involuntary, but incredibly effective) feint which caught Napoleon completely off-guard on the next day.

The 71-years old Austrian Commander-in-Chief, Michael Friedrich Benedikt Baron von Melas, instead ordered the just-retreated troops to cross the river again in the dead of night – and to do so without lighting any fire so as not to alarm French vedettes. However, there apparently were serious problems in moving such a large number of troopers across the single (?) bridge on the Bormida, and the first morning lights saw only a small portion of Melas’ infantry having formed on the far side of the river.

What I’m trying to demonstrate here is that Marengo wasn’t at all a straight and fair pitched battle, or a contest between high military geniuses at their best. Rather, it was the result of several judgment errors, communication failures, improvisation and blind luck (or lack thereof) on both sides. Due to this, I doubt that any ‘classic’ tabletop wargame, however detailed, could model the whole situation in any meaningful – let alone entertaining – way. I wager something like Engle Matrix or open Kriegsspiel (both requiring an umpire and involving hidden information, random events and roleplaying elements) would probably get much closer to what commanders really experienced on that June 14^th of almost exactly 221 years ago.

In contrast, my OHW-based Marengo game will have all the details sorted in advance, and there will be no piece of information hidden to the players or determined randomly at the start of the battle. For example, there will be only one bridge in play – that is, the one at Alessandria. This seems to keep outcomes more closely in line with historical reports.

One might ask however, is it realistic to expect such a simple ruleset as OHW to be able to model anything at all regarding a historical battle? My answer is yes: OHW can in my opinion work as a simple, fast ‘toy model’ of a real battle – provided that you feed it with real values in terms of effectives, space, and time. In that case, I think it should be able to represent a general idea of the situation, give a rough assessment of the possible courses of action, and present players with broad-brush, but historically relevant, choices.

But (most importantly for me), it should give an overall impression of how the entire battle looked like: how much space did a division occupy? How many battalions do you need to defend the Fontanone? Why did take so long for the whole Austrian army to cross the Bormida? I think a map-and-block approach is more suited than using figures to model all of the above, or at least to look vaguely similar to the real battlefield:

One last point about the map: there are a number of open issues regarding terrain and how it impacted on the battle’s evolution. The wineyards were probably of a type that completely impeded cavalry movements along the W-E axis. The Fontanone’s banks were soft and swampy from recent showers and rendered the single bridge at Marengo a lot more important than one might think at first glance. The ground itself wasn’t as billiard-pool-flat as it’s today, after 80 years of mechanised agriculture. All of these issues will be considered in a future post; for the moment, I’m only interested in the general size and shape of the battlefield.

As a first move to reduce complexity, I’ve decided to crop the playing map to a square portion of the battlefield which saw the most intense action, and this is the result (I’ve added a scale in toises in the upper left corner; a toise is around 1.9 metres, and the map covers a locale of around 6.5 x 6.5 kilometres).

Step 2 – Orders of Battle and how to represent them (size does matter).

The next step is to find historical OOBs and to convert it into OHW units. I’m not interested in details and troop types yet – I only want to get an idea of force/space ratios, frontages, etc… which immediately brings to the fore the issue of scale and a ton of practical issues I’ll elaborate on later. Let me explain. Marengo is not a large battle by Napoleonic standards, with around 30k combatants per side. The one reproduced below is a typical XIX century situation map for the battle – there are many of them available online. Judging from their frontages (and their number), those tiny rectangles must be regiments, or demi-brigades, or huge battalions, or any formal classification for a total of around 1500-2500 foot soldiers or around a third that many mounted troopers. It seems to make sense to have these as the actual playing pieces in our wargame.

Now, One Hour Wargames’ RAW are (apparently) agnostic about scale. But no wargame I’m aware of is really scale agnostic – not even those who proclaim themselves as such. Projectile weapons range is where to look first: any kind of specified maximum/effective range for missiles (even if it’s ‘zero’) intrinsically implies a length scale. In horse and musket OHW, infantry and artillery ranges are 12” and 48” respectively – while allowed unit frontages are between 4” and 6”. Even if you assume those figures to correspond to extreme musketry and cannonball ranges (say, around 300m and 1,2 km?) and use the widest possible unit frontage, this equates to assuming our playing pieces represent 150m of linearly deployed troops – that is, largish battalions at most. Of course, if you instead assume those 12” and 48” to represent effective ranges, figures drop by between 2 and 4 times, thus making one OHW unit comprise several companies at most.

With around 60000 soldiers in the battle, it’s easy to see how this is not a viable approach. We need to increase the represented effectives by around 400%, and – consequently – to reduce musketry and artillery ranges by the same token. But I’ll leave the mechanical amendments to movement and firing ranges to a future post; for the moment, let’s just define the size of the ‘chunks’ we’ll divide each army into, both in terms of effectives and actual measures on the table.

As a preliminary consideration, I’ll note that OHW uses inches for all measurements, but it’s trivial to instead use any other unit of measure to scale down (or up) the physical representation of the game on the table, with centimetres being a popular option for ‘pocked-sized’ games. I’ll continue to express all measurements in inches to remain compatible with the RAW, but I’m really meaning generic “OHW length units” instead. I already know for sure that I won’t use actual inches, since at 6” per regiment I’d need half a tennis court to play even on my cropped Marengo map. My amendments will be based on the following sizes/frontages/ranges assumptions:

·       The average frontage occupied by one soldier in a formed infantry unit is assumed to be around 50-60cm

·       The average frontage occupied by one cavalryman in line is assumed to be around 100-120cm

·       Effective musketry range is assumed to be 125m - a broad generalization to include fog of war, inaccuracy… but also the often overlooked fact that even a 5% hit rate is already devastating if you think about it!

·       Skirmishers/sharpshooters are assumed to deploy around 250-300m forward of their parent units, and their shooting to have a longer effective range than massed infantry’s. Due to this, they can start to engage enemies at around 500m forward of a massed infantry unit’s position.

·       Effective artillery range is assumed to be 1000m, extended to 1500m due to bounce in appropriate terrain.

·       Line infantry units will represent a demi-brigade, regiment, huge battalion or equivalent formation comprising around 1500-2500 troopers. Light infantry units represent around half that number, cavalry more like one third, while artillery units represent around two batteries with accompanying caissons, infantry and horses.

All things considered then, I will use a scale of 3 “OHW units” (inches in the RAW) = 125m (or around 65 toises if you are an history nerd like me). This equates to all units having a frontage of 250m.

It’s important to note that, given the above figures, not all of the effectives in a given unit are assumed to be always lined up in a continuous line. The standard 6” frontage of units is intended to represent the space occupied by e.g. a couple of infantry battalions deployed either in line (side by side), or in more compact formations interspersed with the open space necessary to maneuver them effectively. For simplicity’s sake, frontage remains the same for all (implicit) combat formations including ordre mixte and attack columns; columns of route will be represented differently (more on this in a future post).

Formations will not be explicitly represented. It's assumed that officers are constantly trying to keep their men in the most tactically sensible formations; their varying degree of success in doing so is represented by their – and the enemy’s – attack rolls. Regarding line infantry in particular, the assumption is that most of the movement represented on the table is done in some form of columnar formation, e.g. by grand division. Column of route by half company or even narrower are instead assumed for road movement. Infantry units are assumed to deploy into line as part of their firing action (which, as in the RAW, cannot be combined with ‘standard’ movement).

What about units depths then? Well, there are some surprises. The depth of a cavalry unit in 2 ranks is around 6m, and that of a massed infantry unit in 3 ranks less than 2m – both of which are vanishingly small on this scale, corresponding to something like 0,2 inches assuming a 6” frontage! This is practically impossible to represent on the table, even if using the thinnest blocks/counters (let alone miniature bases…). However, as I said above, units are not always assumed to be fully lined up, and infantry in particular will have progressively deeper formations when deployed in ordre mixte, column of grand divisions, column by company, etc… According to this, I will use a default depth of around 50m to accommodate for most non-route formations and/or the space all regiments in successive lines would avoid not to hinder frontliners’ maneuvers. Columns of route, being often 4-8 men walking astride, were basically a line moving sideways, and they will be represented as such (details will follow in a future post).

Artillery is something of a surprise, though. The depth of an artillery battery including reserve caissons was something like 150-200m! This corresponds to a depth of around 4” in OHW terms, which starts to be both non-negligible and practically feasible to be represented on table.

Putting it all together

So that’s what we have so far, in OHW’s native length units (inches):

Unit Type	Avg. effectives	Frontage	Depth
Formed infantry	2000	6”	≈ 1”
Light infantry	1000	6”	≈ 1”
Cavalry	750	6”	≈ 1”
Artillery	≈ 16 guns	6”	4”

 And that’s what they would look like on the map, at the correct scale. I’ve included examples of all four unit types: French line infantry, light infantry and cavalry units in plausible starting positions for Gardanne’s, Chambarlhac’s, Kellerman’s and Champeaux’s men; plus two Austrian artillery units in their alleged June 13^th evening positions.

This is already starting to look like the real thing! One non-trivial issue remains, though: in OHW scale (inches), the map above is exactly 160x160”, an unpractical size for (most?) dining room tables. The trivial solution is of course to reduce the physical footprint of units – that is, making one “OHW unit” to correspond to something smaller than 1”. Centimetres are still not small enough – printing a 160x160 cm map isn’t exactly trivial. Using 1 OHW inch = half a cm is doable, requiring a perfectly reasonable 80x80 cm map and units with a frontage of 3 cm. Myself, I’ve decided to go as small as practically possible, which I’ve found to be only a tad smaller: my blocks will have 2.5 cm wide frontages and my map will be around the size of a typical DBA mat.

In the next post, I will detail my amendments to OHW on the crucial issue of movement and terrain.