Battle of San Marcial At the Battle of San Marcial , 31 August 1813 , the Spanish Army of Galicia under General Freire turned back Marshal Nicolas Soult ' s last major offensive against the Marquess of Wellington ' s allied army . Background . Wellington approached San Sebastián in the aftermath of the Vitoria campaign and put the city under siege in July 1813 , aiming to reduce the important coastal fortress while the French army retired east , nursing its wounds from Vitoria . San Sebastián and Pamplona sat on Wellington ' s flanks , guarding the approaches to the French border , and needed to be pried from French hands before the allies could pursue operations into France . However , it appears Wellington misjudged the resourcefulness and determination of the French garrison and its talented commander , General of Brigade Louis Rey . British assaults sustained very bloody repulses , losing 600 killed in a 26 July attack . Before Wellington could organize a new effort , news reached him that Soult had rebuilt the French field army and reappeared to the east — weeks earlier than Wellington had believed possible — and the allies broke off the siege to confront him . While Wellington faced off against Soult in the Battle of the Pyrenees , Lieutenant General Graham maintained a blockade of San Sebastián and prepared for the resumption of the siege on 26 August . A line of light fortification s was put up to guard against a relief effort by Soult , and a strong cordon was established up to the banks of the Bidasoa . In addition to the Anglo - Portuguese divisions at Vera , Lesaca , and Irun , this screen included the Spanish 3rd , 5th , and 7th divisions on the San Marcial heights , as well as two brigades of the 4th division in reserve ( forming Freire ' s Fourth Spanish Army , or Army of Galicia ) . After four weeks of rest Soult was , in fact , preparing one last push toward San Sebastián , concentrating all his nine divisions at Ainhoue for an attack in the vicinity of San Marcial . Neither the French nor the Spanish troops were in perfect spirits ; the French were demoralized by their recent retreats and their heart was not in the coming fight , while Freire ' s ragged troops , neglected by the Spanish commissariat , had not enjoyed full rations in several days . Behind them , the allied army was locked in a terrible struggle for San Sebastián that would cost it 2 , 376 dead and wounded on 31 August alone . Battle . In an early morning mist , seven French divisions crept toward the Bidassoa on August 31 , fording the river under cover of their guns . The allied positions at Vera and Irun were surprised and overrun but not before alerting Freire , who drew his troops into a line on the heights . The Imperial columns lost all cohesion as they climbed over the difficult terrain , reaching Freire in a confused mass . The Spaniards welcomed them with a scathing volley and , advancing with fixed bayonets , rolled Soult ' s leading divisions back down the hill . Soult rallied the broken units at noon and committed fresh troops to a second assault on the heights , but the line of Spanish bayonets held firm against his final assault and the faltering French were badly beaten . Unable to keep his men from retreating back over the river , Soult ordered a withdrawal back to Irun and called off his offensive without having met a single red coat : When , in the last laps of battle , Freire requested reinforcements from the British to shore up his battered line , Wellington replied , " As he has already won his victory , he should keep the honour of it for his countrymen alone . " San Sebastián fell after a fearful battle later that day , and Soult retreated into French soil . Combat of Vera . During the afternoon , a violent thunderstorm struck the area and brought in torrents of rain . By the time General of Division Bertrand Clausel ' s rearguard reached the fords over the Bidassoa , there were six feet of water over them . The rearguard commander , General of Division Edmé - Martin Vandermaesen , led 10 , 000 men upstream to Vera ( Bera ) . The long bridge at Vera would only admit a column three or four men wide , but it was the only possible escape route . A 70 - man company of the green - jacketed , rifle - armed British 95th Regiment under Captain Daniel Cadoux held the village with two sentries posted at the bridge . At 2 : 00 am on 1 September , the French successfully rushed the bridge , but could go no farther . In the heavy rain , the muskets of the French would not fire so they had to resort to the bayonet . Meanwhile , the British riflemen were secure with dry gunpowder in loopholed buildings . Over and over , the French tried to rush the buildings at the end of the bridge , but they were mown down in heaps by rifle fire . Cadoux sent for assistance from a brigade of the Light Division that was camped a mile away . Incredibly , Major General John Byne Skerret refused to send help . Instead , he ordered Cadoux to withdraw . The captain refused to obey and held his post against repeated attacks . At length , Skerret repeated his order to withdraw . Cadoux , who had only lost his two sentries , reluctantly prepared to obey . However , it was now dawn , the rain had stopped and the gunpowder of the French was now dry . As the green - jackets abandoned the buildings , the French opened a terrific fire . Cadoux and 16 of his men were killed and more wounded . Abandoning their artillery , the French filed over the now - undefended span to escape from the trap . Vandermaesen lay among the dead . Aftermath . The battle marked the end of Soult ' s once redoubtable fighting force : " war - weary and despondent , Soult ' s divisions had lost all heart and , except in a few inspired flashes , were never again to fight with their once customary skill and zeal . " The Spanish performance at San Marcial , together with that of General José Zayas ' s Division at the Battle of Albuera and General Francisco Castaños ' s army at the Battle of Bailén , were among their best efforts of the Peninsular War . The next action would be the Battle of the Bidassoa on 7 October .