Battle of Ocana

The Battle of Ocana or Battle of Ocaña was fought on 19 November 1809 between French forces under Marshal Nicolas Jean de Dieu Soult and King Joseph Bonaparte and the Spanish army under Juan Carlos de Aréizaga, which suffered its greatest single defeat in the Peninsular War. General Juan Carlos de Aréizaga's Spanish army of 51,000 lost nearly 19,000 killed, wounded, prisoners and deserters, mostly due to the French use of their cavalry.

William Napier writes: "The Spaniards came on at a trot, and Sebastiani directed Paris, with a regiment of light cavalry and the Polish lancers, to turn and fall upon the right flank of the approaching squadrons, which being executed with great vigor, especially by the Poles, caused considerable confusion, with the Spanish general endeavored to remedy by closing to the assailed flank."