Battle of the Bidassoa ( 1813 ) In the Battle of the Bidasoa ( or the Battle of Larrun ) on 7 October 1813 the Allied army of Arthur Wellesley , Marquess of Wellington wrested a foothold on French soil from Nicolas Soult ' s French army . The Allied troops overran the French lines behind the Bidassoa River on the coast and along the Pyrenees crest between the Bidasoa and La Rhune ( Larrun ) . The nearest towns to the fighting are Irun on the lower Bidassoa and Bera on the middle Bidasoa . The battle occurred during the Peninsular War , part of the wider Napoleonic Wars . Wellington aimed his main assault at the lower Bidasoa , while sending additional troops to attack Soult ' s center . Believing his coastal sector secure , Soult held the right flank with a relatively weak force while concentrating most of his strength on his left flank in the mountains . However , the British general obtained local intelligence that indicated that water levels on the lower river were much lower than the French suspected . After careful planning , Wellington launched a surprise assault which easily overran the French left flank defenses . In the center , his army also won through the French defenses , though his Spanish allies were repulsed in one attack . At the beginning of the fighting , Soult realized that his left flank was in no danger , but he reacted too late to restore his positions on the right . Some French generals were shocked at how poorly their soldiers fought . Background . Operations . In the Battle of San Marcial on 31 August and 1 September 1813 , Soult ' s army was repelled in its final bid to advance into Spain . After a costly assault followed by a brutal sack of the city , the Allies also brought the Siege of San Sebastián to a successful conclusion in early September . A French garrison held out in the Siege of Pamplona which would end in a surrender on October 31 . Wellington determined to create a bridgehead across the Bidassoa River . If successful , his army would be the first Allied army to establish itself on French soil . The British commander also wanted to capture French positions that overlooked the Allied lines on the west side of the Bidassoa . Preparations . Because the French troops had begun to plunder their fellow citizens , Emperor Napoleon ' s Minister of War , Henri Clarke ordered Marshal Soult to defend a position as close to the frontier as possible . He had to hold a front in the Pyrenees mountains . The area was highly defensible , but lateral communications were poor . Deciding that the coastal sector was the strongest part of his line , Soult posted General of Division Honoré Charles Reille and 10 , 550 men to defend that sector . Reille ' s command included General of Division Antoine Louis Popon de Maucune ' s 3 , 996 - strong 7th Division and General of Division Pierre François Joseph Boyer ' s 6 , 515 - strong 9th Division . Maucune held the lower Bidassoa on the Bay of Biscay , while Boyer defended the stream farther inland . Behind them was the entrenched camp of Bordagain and the port of St - Jean - de - Luz . General of Division Eugene - Casimir Villatte ' s 8 , 018 - man Reserve Division held this area . General of Division Bertrand Clausel held the center with 15 , 300 men in the divisions Generals of Division Nicolas François Conroux , Jean - Pierre Maransin , and Eloi Charlemagne Taupin . On the right , near the Bidassoa , stood the " La Bayonette " redoubt . Mont La Rhune ( Larrun ) rose in the center of Clausel ' s sector . His left touched the Nivelle River near Ainhoa . Conroux ' s 4th Division numbered 4 , 962 men ; Maransin ' s 5th Division counted 5 , 575 troops ; Taupin ' s 8th Division had 4 , 778 soldiers and held the area just north of Bera . Soult ' s gunners , sappers , and other troops added up to 2 , 000 and his total forces numbered 55 , 088 effectives . His cavalry was stationed in the Nive valley . Fearing an allied thrust over the Maya Pass and down the Nivelle River to the sea , Soult gave General of Division Jean - Baptiste Drouet , Comte d ' Erlon 19 , 200 men to hold his left flank . D ' Erlon ' s corps included the divisions of Generals of Division Maximilien Sebastien Foy , Jean Barthélemy Darmagnac , Louis Jean Nicolas Abbé , and Augustin Darricau . These troops held a line from Ainhoa to the mountain fortress of St - Jean - Pied - de - Port , covering the Maya and Roncesvalles Passes . Darricau ' s 4 , 092 - man 6th Division was deployed between Ainhoa and Sare ; Abbé ' s 6 , 051 - strong 3rd Division was west of Ainhoa ; Darmagnac ' s 4 , 447 - man 2nd Division held Ainhoa ; Foy ' s 4 , 654 - strong 1st Division held the fortress at the extreme left flank . Wellington had 64 , 000 Anglo - Portuguese infantry and artillery , plus 25 , 000 Spaniards . Since cavalry was of little use in the mountains , the British commander sent most of his horse regiments to the rear , keeping a few light dragoons for patrolling . In order to gain his bridgehead , Wellington had to force a crossing of the Bidassoa estuary . The river was wide and deep at the high - water mark below the Île de la Conference . The French never suspected that there was only 1 . 2 meters of water over the lower fords at certain low tides , a fact that the Allies gleaned from Basque fishermen . Allied intelligence knew that the next low tide was 7 October . The crossing was meticulously planned . Near the lower fords , British engineers built a turf wall near the river . This would shelter Major General ( MG ) Andrew Hay ' s 5th Division during the time before it crossed the river . Wellington positioned five field batteries and three 18 - pdr siege cannon to provide fire support to the attacking infantry . Battle . Allied Army . Arthur Wellesley , Marquess of Wellington ( 89 , 000 , 24 , 000 engaged ) < br > Coastal Sector La Rhune Sector " Note : Only the engaged units are listed . " Bidassoa . At 7 : 25 am the 5th Division launched its attack from near Hondarribia ( Fuenterrabia ) . It came as a complete surprise to the French , who had deployed only Maucune ' s 4 , 000 men to defend six km ( four miles ) of river . Immediately , Hay ' s men gained a foothold at the village of Hendaye and swung two brigades to the right to assist the crossing of MG Kenneth Howard ' s 1st Division . At 8 : 00 am , Howard ' s men , MG Thomas Bradford ' s independent Portuguese brigade and MG Lord Aylmer ' s independent British brigade forded the river near a destroyed bridge at Béhobie . Three Spanish brigades from LG Manuel Freire ' s two divisions ( MG Del Barco and MG Barcena ) crossed farther to the right . Rapidly , the British overran the " Croix des Bouquets " position and the Spanish captured Mont Calvaire at . The entire ridge on the French side of the river fell into Allied hands at the cost of only 400 casualties . With the high ground in his possession , Wellington suspended the attack . That morning Soult was absorbed in watching Henry Clinton ' s 6th Division advancing from the Maya Pass . The division ' s Portuguese brigade boldly seized the Urdax ironworks , losing 150 men in the combat . Soult suddenly realized the operation was only a demonstration . He rode off to his coastal sector but he was too late to help Reille . La Rhune . The toughest fighting of the day occurred in Clausel ' s sector . Lieutenant Colonel John Colborne ' s brigade of Charles Alten ' s Light Division attacked " La Bayonette " at . The French charged downhill and drove back the green - jacketed skirmishers of the 95th Rifles Foot . Suddenly the 1 / 52nd ( Oxfordshire ) Regiment of Foot ( Light Infantry ) appeared out of the trees and quickly turned the tables . Following closely behind the retreating French , the redcoats of the 52nd overran the redoubt with surprising ease . Meanwhile , MG James Kempt ' s other Light Division brigade and Brigadier General Francisco de Longa ' s Spanish division attacked up two spurs of La Rhune to secure some positions . To their right , Lieutenant General Pedro Girón ' s two Andalusian divisions ( MG Virues and MG La Torre ) attacked the summit of La Rhune . Though the Spanish attacked repeatedly , they were defeated . However , the next day the French abandoned the position to avoid encirclement . Results . In Reille ' s sector , the French lost 390 killed and wounded , plus 60 men and eight cannons captured . In Clausel ' s sector , the French suffered 600 killed and wounded , plus 598 men and nine cannons captured . The British lost 82 killed , 486 wounded , and five missing , or a total of 573 . The Portuguese lost 48 killed , 186 wounded , and eight missing , or a total of 242 . The Spanish suffered the balance of the 1 , 600 total Allied casualties . The defeat lowered morale in Soult ' s army . Except at La Rhune , French troops did not obstinately defend their positions . Villatte commented , " with troops like these we can expect only disgrace . " Soult made Maucune the scapegoat , dismissed him from his division , and sent him to the rear . After the battle , some of the Allied troops indulged themselves in the looting of French homes and towns . Wellington came down harshly on British troops caught plundering . He felt sympathetic to the Spanish , who had seen their nation ravaged by French soldiers , but he determined to tolerate no looting for fear of provoking a guerilla war . During the follow - up to this victory , Spanish troops seized the Sainte - Barbe Redoubt at , 1 . 4 km south of the village of Sare . On 12 October , Conroux ' s division recaptured the fort from its garrison of La Torre ' s division and drove off a five - battalion Spanish counterattack . French casualties are estimated at 300 , while the Spanish lost 300 killed and wounded , plus 200 captured . The next engagement was the Battle of Nivelle on 10 November 1813 . Postscript . An inaptly named Lieutenant Gentle Vickers of the 3rd battalion of the 95th Regiment was severely wounded in this action . He survived to take part with two companies of the 3 / 95 and Colborne ' s 52nd Regiment in the famous assault on the flanks of the advancing Imperial Guard that triggered the final rout at Waterloo .