The Battle of Maipu April 5th, 1818

So today is 201 years since the Patriot victory at Maipu by the Argentine-Chilean army commanded by Jose de San Martin.

Some time ago I ran a game at Cold Wars based on this battle as it was the revolutionary wars were the convention theme.

This is the scenario used for that convention for Sam Mustafa’s rules Lasalle:

Setting: Maipu – South of Santiago, Chile – 5 Apr 1818

Historical Context

Since 1810 the Spanish colonies in South America had embraced open revolution against Spain. The United Provinces of the South ( Argentina and Uruguay ) had actually achieved independence by 1815, but their war against the Royalist forces in the northern territories of Argentina and Bolivia had been unsuccessful. After the defeat of a Patriot army at the battle of Sipe Sipe ( or Viluma ), the only thing preventing the royalists from regaining control of the River Plate was the guerrilla warfare done by the Gauchos, but the future appeared uncertain.

Back in 1812 a creole career military officer had return to South America after serving Spain in the wars against Napoleon. He was abandoning a promising career in the Spanish military after being promoted for his role as ADC to Coupigny during the battle of Bailen, his new objective was to return to his native land and lead contribute to the Patriot efforts.

By 1817 San Martin had realized that Buenos Aires attempts to defeat the Royalists forces in the north were ill conceived and that the way to achieve this would be to cross the Andes and liberate Chile and from there initiate an amphibious operation to Peru, the heart or the Royalist presence.

With this in mind San Martin gathered an Army and crossed into Chile in early 1817, defeating the opposing forces in Chacabuco. However after the initial victory he had to return to Buenos Aires to secure further resources for the campaign.

While San Martin was in Buenos Aires the war in Chile became more complicated due to the arrival of the “expedicionarios” reinforcements from Peru, which included veteran peninsular units.

Now in 1818, with San Martin back in Chile, Royalist and Patriots forces were moving towards each other once again.

The Royalists took first blood when on March 19th the Royalist Brigadier Jose Ordonez, a skilful Spanish commander that had been a comrade of San Martin in the peninsular war, convinced the Royalist general, Mariano Osorio, to initiate a night offensive on the Patriot army that had besieged them in the city of Talca.

The Patriot army was manoeuvring to prepare themselves for the attack, alerted by spies, but they were caught before they could deploy, this was the battle of Cancha Rayada. The Patriot army routed from the field but calm and ordered performance by Las Heras insured that the main body of the army retreated in good order preventing a total defeat, nevertheless panic spread among the Patriots and morale was very low.

A few weeks later San Martin had managed to regroup a good portion of the patriot army and was now ready to face Osorio’s army that was moving towards Chile.

O’Higgins was left in Santiago with some troops fortifying the city in case disaster should occur and the main body of the army left with the Argentine general to face the enemy at a valley close to the river Maipo.

Some of San Martin officers were not very convinced with facing the army that had surprised them at Cancha Rayada in a set piece battle in open terrain; Brayer a French officer in Patriot service requested to be excused and San Martin dismissed him declaring: “The last drummer in the army has more courage than your generalship, you may leave then but you should know that in the next hours the fate of Chile will be decided.”

The troops deployed on the field by around 11:30AM.

The Royalists deployed the Grenadier and Cazadores companies together with 4pdr guns and the Frontier Dragoons on the left flank under command of Primo de Rivera while the fusilier companies and the 8 pdr guns were deployed in the centre, anchored on the elite Burgos battalion and with their light dragoons securing their right flank.

San Martin deployed Las Heras division with 3 infantry battalions, Blanco Encalada’s horse artillery and the horse grenadiers to his right facing Primo de Rivera, and Rudecindo Alvarado with another 3 infantry batallions in the centre supported by de la Plaza 8pdr Andes artillery and Brogono’s 4pdr artillery in support with the patriot light cavalry protecting their flank, but he also deployed Hilarion de La Quintana’s division in reserve with another 3 infantry battalions.

The armies were roughly similar in numbers since although the Patriots presented more battalions most of these were under strength not reaching 400 men each while the royalist expedicionarios battalions were at full strength of 1000 each.

And so one of the bloodiest battles in the war of Independence was about to begin.

The Field of Battle

Given that it was going to be a big battle, that I could have players that didn’t know the rules and that the heaviest guns in the game would be medium artillery ( 8pdrs ) I decided to set up 12 BW in rather than the 6 BW to skip the first turn for each side since experienced Lasalle players will know to deploy in march column and go in but new players are not familiar with this.

For deployment I didn’t want to force the historical deployment so I divided the armies as you saw above in the historical divisions and ask each side to tell me in secret if they would deploy all three divisions or keep one in reserve.

The division in reserve would be allowed to be deployed starting even from turn 1, no roll needed but it would deploy 6 BW in and deploy at the end of the turn. This meant that by using a reserve you could observe your enemy deployment and plan a bit before deploying those troops.

If one side was deploying fewer divisions that then other then each side would deploy one division and alternate starting with the side deploying more divisions, if they were deploying the same number they would alternate divisions starting with the Royalists.

Each side gets a command post instead of a C-in-C.

The opposing forces for Lasalle Napoleonic rules:


The Royalist Army ( playing as defender )

Battle objectives:
Rout the Patriot army. Failing that inflict more casualties and retain possession of the “Lo Espejo” high ground. Royalists deploy first.


The Patriot Army (playing as the attacker )

Battle objectives:
Rout the Royalist army. Failing that inflict more casualties and retain possession of the “Lo Espejo” high ground. Patriot starts game with Initiative

Victory Conditions

For victory conditions I established a victory point system

+1vp for eliminating 30%+ of the enemy
+1vp for eliminating 50%+ of the enemy
+1vp for eliminating 60%+ of the enemy
+1vp for overrunning the enemy command post
+1vp for holding the “Lo Espejo” high ground, ie the hill where the royalist
starts the game, this meant that the Royalists started the game with +1 VP
+1vp for having the cavalry advantage as per Lasalle ( this gavea +1 VP to
the patriots from the start)
+1vp if the enemy army breaks ( both sides would check on 5D6 and the
defender objective would simply give 1vp as stated above not force a beak
test at 4VP )

Dif in VP 0 -> Tie , 1-2 Marginal Victory , 3+ Decisive Victory

Note that the system gives the same Lasalle result in most cases except in those extreme cases that sometimes annoy people, and also pushed both sides to keep fighting till the end. I don’t have big issues with the Lasalle system when you are playing many games but for a one time convention game I want to avoid the quirky results. Note also that when an army breaks the opponent gets a +1VP but you still do VP calculation to see if you won. The enemy could leave the field but if you didn’t cause enough casualties and you don’t have cavalry advantage for example, it might not even be a victory if you yourself took heavy casualties and were simply lucky not to break.

Special Rules
  • As I mentioned the balance of forces was roughly the balance for attacker defender that we find in Lasalle AB, but both sides would get three subcommanders. Also there would be no overall commander, there was a command post on each side that was assigned a fixed position and that could command units with the “I’m with stupid rule”.

Notes

To play this battle using Lasalle I have converted the army composition and quality from Fletcher’s Liberators into Lasalle stats. I have adjusted quality gradings in order to get armies that appear to be balanced when compared to typical attack and defense armies generated with the Army Builder System using a proxy point system for the army builder available from the Lasalle forum.

The armies show the typical proportions that you will face when fighting a Lasalle game with on core and one support per side ( roughly ).

In the battle the Royalist forces took a defensive position probably due to having inferior cavalry, and so in the battle the royalists will be considered the defender.

The armies will be divided in three divisions ( brigade size actually for European standards ) according to the historical organization presented in the battle.

Also I want to thank Steven Balagan since he posted my scenario in his blog and after a hard drive crash it was the one location from where I could recover it. You should visit his fantastic blog here:
https://balagan.info/

Also we need to mention Grenadier Productions and the fabulous supplement Liberators!
http://www.grenadierproductions.com/

Here are some pictures from when I ran this game at my local convention in Austin where the game won as best game of the convention