Battle of Ocaña The Battle of Ocaña ( or Ocana ) was fought on 19 November 1809 between French forces under Marshal Nicolas Jean de Dieu Soult , Duke of Dalmatia 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 . The strategic consequences were also devastating , as it destroyed the only force capable of defending southern Spain ; the area was overrun over the winter in the Andalusia campaign . Background . Maneuvers . The Spanish campaign in the autumn of 1809 called for their armies to lunge at Madrid from both north and south . They called for assistance from Arthur Wellesley , Viscount Wellington , but after experiencing a lack of cooperation from the Spanish during the Talavera campaign the British general refused . The French were nearly surprised by the southern thrust . By 9 November , the southern army was within 35 miles of Madrid with only 7 , 000 French troops blocking them . Then Aréizaga lost his nerve and halted for three days . He then pressed on toward Madrid but ran into two French divisions and pulled back . Several days of fruitless countermarching found the thoroughly alerted French concentrated and moving to intercept the Spanish army . Spanish Army . Aréizaga commanded 51 , 000 men in eight infantry and four cavalry divisions , with 60 cannon manned by 1 , 500 artillerists . Other authorities give the Spanish 60 , 000 or 56 , 500 men French Army . King Joseph led the French army in name only . Actual command over the 24 , 000 infantry , 5 , 000 cavalry , 1 , 500 artillerists and 50 cannon was exercised by Marshal Nicolas Soult . Two army corps , three cavalry divisions and the Central Reserve formed core of the army . Battle . Cavalry action . On 18 November , one of the largest cavalry actions of the Peninsular War took place . Three of Freire ' s divisions , 4 , 000 horsemen , attempted to clear a route of retreat for the Spanish army . The French deployed with Paris ' s light cavalry in the front line and Milhaud ' s dragoons in the second line . Paris charged , broke the Spanish first line , and was checked when Freire brought up his reserves . At this juncture , Milhaud ' s dragoons attacked and drove the Spanish cavalry from the field . The French lost less than 100 men , while Spanish losses were in the hundreds , with 80 captured . William Napier writes of the cavalry action before the battle : " 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 . " Positions . West of Ocaña town , Aréizaga placed José Pascual de Zayas y Chacón ' s Vanguard and Rivas ' s cavalry . From Ocaña to the east , the Spanish commander aligned his center and right . The right flank , which hung in air , was held by Freire ' s remaining three cavalry divisions . From there to Ocaña , Luis Roberto de Lacy , Castejon , Pedro Agustín Girón and Vigodet held the front line . Their battalions were arranged in a double line . In reserve behind Castejon stood Jacome ' s men , Zerain supported Giron and Copons backed up Vigodet . The Royal Guard and one brigade of Dessolles stood north of Ocaña , facing across a deep ravine . The next unit to the east was Louis Rey ' s brigade of Dessolles . Gazan and Girard of the V Corps , Leval and Werlé of IV Corps , and the cavalry completed the line to the east . Soult massed 30 cannons near Dessolles and the V Corps ' positions . Battle . On 19 November , the massed battery pounded the Spanish center as Leval attacked Castejon and Werlé went in against Lacy ' s division . At first the Spanish swung their line back . Then , as the IV Corps halted to wait for artillery to be brought up , the two Spanish divisions surged forward into musket range and opened fire . The Dutch , Germans and Poles began to edge rearward . Soult ordered up Girard ' s division to support the wavering IV Corps battalions . While this was going on , Milhaud ' s dragoons , supported by Woirgard and Paris , moved rapidly toward the vulnerable Spanish right flank . Screened by olive groves , they suddenly appeared in front of Freire ' s command . The French charged and soon routed the Spanish horsemen . Milhaud , Paris and Woirgard neatly wheeled their squadrons and tore into the unprotected flank of Lacy ' s infantry . Soult sent the French line forward . The massed battery savaged the Spanish line with renewed fury . Faced by the threat of infantry pressing their front while cavalry slashed into their flank , the Spanish divisions collapsed one after another and bolted for the rear . At this crisis , Dessolles and the Royal Guard dashed across the ravine and burst into Ocaña , severing the Spanish left from their disintegrating center and right . As the Spanish army streamed away to the south , only Zayas ' s division remained intact to cover the retreat . Soult ' s cavalry pressed the pursuit and broke Zayas later in the day . Results . The French captured 14 , 000 Spaniards , 50 cannon , 30 flags and the entire baggage train . Another 4 , 000 were killed and wounded . French losses were 2 , 000 killed and wounded . Paris was killed and Girard wounded . This catastrophe temporarily laid Spain open to French domination . The northern Spanish army was beaten a week later at the Battle of Alba de Tormes . The way was open for the French conquest of Andalusia .