Battle of Garcia Hernandez In the Battle of Garcia Hernandez on 23 July 1812 , two brigades of Anglo - German cavalry led by Major - General Eberhardt von Bock defeated 4 , 000 French infantry led by Major - General Maximilien Foy . In what would otherwise have been an unremarkable Peninsular War skirmish , the German heavy dragoon s achieved the unusual feat of breaking three French square s , those of the 6th , 69th and 76th Line , routing the entire French force with heavy losses . Background . The previous day , the Allied army commanded by Arthur Wellesley , 1st Duke of Wellington had won a decisive victory over a French army led by Marshal Auguste Marmont in the Battle of Salamanca . Foy ' s division was the only French unit not engaged in the battle and it was acting as rearguard on 23 July . Battle . Bock ' s 770 - strong heavy cavalry brigade , consisting of the 1st and 2nd King ' s German Legion ( KGL ) Dragoons , led the pursuit of the French . In support of Bock were the 1 , 000 troopers of George Anson ' s British light cavalry brigade ( 11th , 12th and 16th Light Dragoons ) . As the Anglo - Germans approached , Maj - Gen Curto ' s French cavalry fled . Foy arranged his eight battalion s on a hill in square . He had two battalions each of the 6th Light , and the 39th , 69th and 76th Line Infantry Regiments . Bock ' s dragoons charged a square belonging to a battalion of the 6th Light . The French held their fire too long . Their volley killed a number of horsemen , but a mortally wounded horse carrying a dead dragoon crashed into the square like a battering ram . The horse fell , kicking wildly , knocking down at least a half - dozen men and creating a gap in the square . Captain Gleichen rode his horse into the gap , followed by his troopers . The square broke up and most of the men surrendered . A second square farther up the hillside was soon charged . Shaken by the first square ' s disaster , the men flinched when the dragoons rode into them . Soon the men in the second square were running for their lives , except those who surrendered . Foy quickly pulled back the rest of his troops . Anson ' s horsemen mopped up the battlefield . Results . Foy lost 200 killed and wounded , and 1 , 400 captured . Bock lost 54 killed and 62 wounded . The very high proportion of killed to wounded was due to the " deadly effect of musketry at the closest possible quarters . " Another authority gives 52 Germans killed , 69 wounded and 6 missing and 1 , 100 total French casualties . Commentary . The breaking of a steady square was a rare event . A French infantry battalion in square formed up in a bayonet - studded hedgehog either 3 - ranks or 6 - ranks deep . ( A British square was 4 - deep . ) If a square stood its ground without flinching and fired with effect , it could withstand the best cavalry . When infantry squares were broken by cavalry in the Napoleonic Wars , it was usually because : At Garcia Hernandez , the last event occurred with the first square , leading to the extraordinary accident of a dead horse and rider smashing into the square which was then exploited by the following cavalry . The second square likely panicked at the extraordinary sight of the first square being torn apart . Culture . This skirmish is depicted in Bernard Cornwell ' s Novel , Sharpe ' s Sword . The battle was also shown in Suzanna Clarke ' s Jonathan Strange and Mr . Norrell , while Jonathan Strange is serving under the Duke of Wellington .