After the French Army of Portugal's heavy defeat at Salamanca in late July, it began to meander it's way back east, taking a wide berth across the the top of Madrid. To the south of Madrid, and initially unaware of the French defeat at Salamanca, was Joseph Bonaparte, Napoleon's brother and newly installed King of Spain. He had a an army of 16,000 men with him and on hearing of the defeat decided to make a dash to Madrid, but when he realised Wellington was still stationary he positioned himself west of the city in his path.
Wellington, wanting to ensure his men were properly supplied at all times to maintain discipline, delayed his pursuit until his wagon trains caught up and were able to reequip his men with ammunition and rations. By the time he set off he had two choices, to pursue the mauled French Army of Portugal to the north or to capture the capital city. He decided to send a smaller force north to keep the French moving away while his main army would advance on Madrid. Joseph Bonaparte opted to pull back to the city and it was on the 11th August that the vanguard of Wellington's army ran into the rearguard of Joseph's army which had been ordered to delay the advancing British-Portuguese army.
ORDERS OF BATTLE - we usually provide a numbers of men to models comparison, but as there are so many different Napoleonic rules out there with vastly differing unit sizes we are simply going to list units for you to select your own preferred unit size.
General de Division Anne-Francois-Charles Trelliard (Overall commander of French forces at the battle) - excellent leader, inspiring, veteran
4 regiments of line dragoons - heavy cavalry, well trained, veteran, sword and dragoon muskets
(13th, 18th, 19th & 22nd dragoon regiments)
General de Brigade Guiseppe Frederico Palombibi - excellent leader, reliable, veteran
1 Regiment of Italiene Napoleone Dragoons - heavy cavalry, trained, steady, sword and dragoon muskets
1 Regiment of Westphalian Cheveau-legers - light cavalry, well trained, steady, sword
General de Brigade Chasse - experienced leader, reliable, veteran
1 Battalion of 2nd Nassau Infantry - trained, experienced, musket
1 Battalion of Spanish La Mancha Infantry - trained, unsteady, musket
2 8lb artillery cannon and crew - trained, experienced, steady
Brigadier General Benjamin D'Urban (overall Allied commander at the battle) - experienced leader, veteran
3 Regiments of Portuguese Dragoons - Light cavalry, trained, unsteady, unreliable, sword, dragoon carbine
(1st, 11th & 12th Portuguese Dragoons)
2 6lb artillery cannon and crew - trained, experienced, unsteady
Colonel de Joncquieres - excellent leader, inspiring, veteran
2 Regiments of King's German Legion Heavy Dragoons - Heavy cavalry, well trained, veteran, sword and dragoon muskets
(1st & 2nd KGL Dragoons)
Colonel Colin Halkett
2 Battalions KGL Lights - Regular infantry, skirmish trained, veteran, disciplined, muskets
(1st & 2nd Light Battalions KGL)
2 6lb artillery cannon and crew - trained, experienced, disciplined
Major-General Ponsonby - experienced, inspiring leader, veteran
3 Regiments of British Heavy Dragoons - heavy cavalry, well trained, veteran, sword & dragoon muskets
(5th Dragoon Guards, 3rd & 4th Heavy Dragoons)
THE BATTLE AS IT HAPPENED
Wellington's advance guard arrived at the village of Las Rozas on the morning of the 11th August, the KGL troops dismounted to rest in the village while a few scouts were sent forward with the Portuguese dragoons and four artillery pieces following them in support should trouble be sighted.
Meanwhile, and unaware of the British in Las Rozas, Trelliard's men were entering Majadhonda, as they appeared on the far side of the village they spotted the scouts and behind them, the Portuguese and immediately began to attack.
The first line of four dragoon regiments charged across the plain while D'Urlon attempted to get his Portuguese dragoons to counter-charge. Instead, they turned and fled, abandoning the cannon which were overrun by the French. As the fleeing dragoons reached Las Rozas they galloped into the heart of the village where they attempted to rally in the market square.
The sound of the approaching horses and pistol fire had alerted the KGL units in the village who hurriedly mounted a defense, with infantry fire from the buildings and the cannon quickly positioned supported by dismounted dragoons, blocking entry to the French.
Other KGL dragoons were remounting in the square and with the rallied Portuguese made a counter charge out of Las Rozas and chased the French back towards Majadhonda, this time to be stopped by the Nassau and Spanish infantry who had now formed up with artillery across the road. Their volleys and cannon fire stopped the KGL and Portuguese dragoons, the latter once again fleeing back to Las Rozas while the KGL attempted a more structured fighting withdrawal, as the French dragoons exchanged musket fire from the saddle with them.
Finally as the KGL dragoons had almost been beaten back to Las Rozas, Major-General Ponsonby appeared with his three British heavy dragoon regiments, they had been following the advance guard along the road and had cantered forward when hearing cannon fire. The fresh British cavalry charged in to the French and Italian dragoons, with the now exhausted KGL dragoons attempting to join in. The melee was furious and intense with the French initially holding their ground until it became apparent that more British troops would soon be arriving behind Ponsonby, at which point the French withdrew, passing through Majadhonda and catching up with the main army as it pulled back to Madrid.
Although the British ultimately captured the battlefield, Trelliard had succeeded in delaying their advance for precious time allowing the main French army to distance itself from Wellington's force.
Wellington praised his KGL men for such gallant fighting, while the Portuguese were rated as unreliable and under orders to only ever be used if alongside British cavalry who could show them how to fight.
This is a relatively small battle with only 2,000 - 2,500 men on each side and would lend itself to skirmish rules as well as standard rules like Black Powder.