Battle of Boulou The Second Battle of Boulou , 29 April to 1 May 1794 , saw the French Army of the eastern Pyrenees led by Jacques François Dugommier attacking the joint Spanish - Portuguese Army of Catalonia under Luis Firmin de Carvajal , Conde de la Union . The decisive French victory resulted in the French regaining nearly all the land they lost to the Kingdom of Spain in 1793 . Le Boulou is on the modern A9 highway , 20 km south of the department capital at Perpignan and seven km north of Le Perthus on the France - Spain border . Background . 1793 . The year 1793 was a difficult time for the poorly trained French forces defending Rousillon against the Spanish army of Captain General Antonio Ricardos . The Siege of Bellegarde concluded in June with the French surrender of the Fort de Bellegarde , which dominated the key Pass of Le Perthus through the Pyrenees . However , Ricardos was repelled in the Battle of Perpignan on 17 July . The French army revived again under General of Division Eustache Charles d ' Aoust to deal their enemies a sharp reverse at the Battle of Peyrestortes on 17 September . Five days later , Ricardos defeated the French at the Battle of Truillas . Subsequently , the Spanish general fell back to the valley of the Tech River where he repulsed a series of French attempts to drive him back into Spain . D ' Aoust tried and failed to oust the Spanish from Le Boulou on 3 October . In the Battle of the Tech ( or Pla del Rey ) from 13 to 15 October , Ricardos bloodily repulsed the attacks of General of Division Louis Marie Turreau . D ' Aoust was defeated again in his 7 December attack on Villelongue - dels - Monts . The Spanish seized the port of Collioure on 20 December . New commanders . Fresh from his victory at the Siege of Toulon , General of Division Jacques François Dugommier arrived to lead the army on 16 January 1794 . He began a complete reorganization of the army , setting up supply depots , hospitals , and arsenals , and also improving roads . After getting reinforcements from the Toulon army , Dugommier ' s field army numbered 28 , 000 . These troops were supported by 20 , 000 garrison troops and 9 , 000 green volunteers . He formed his field army into three infantry divisions under Generals of Division Dominique Catherine de Pérignon , Pierre Augereau , and Pierre François Sauret . There was a 2 , 500 - strong cavalry division led by General of Division André de la Barre and a reserve headed by General of Brigade Claude Perrin Victor . During the winter , Ricardos travelled to Madrid to plead for reinforcements . He died there of pneumonia on 13 March 1794 . Ricardos ' designated successor , Captain General Alejandro O ' Reilly died on 23 March before he could reach the front . In the interim , Lieutenant General Jerónimo Girón - Moctezuma , Marquis de las Amarilas assumed leadership over the Army of Catalonia . But in late April , Lieutenant General Luis Firmín de Carvajal , Conde de la Unión finally accepted command of the army , after refusing it three times . Battle . Dispositions . De la Union deployed his 20 , 000 - strong army to hold the Tech valley , with defences both north and south of the river . Lieutenant General Eugenio Navarro commanded the right flank division , whose positions included Collioure and Port - Vendres on the coast . The 8 , 300 - man centre division of Lieutenant General de las Amarilas held strongpoints at Le Boulou , Montesquieu - des - Albères and the Camp of Trompettes . Lieutenant General Juan Miguel de Vives y Feliu with 5 , 500 soldiers of the left division defended Céret , where de la Union installed his headquarters . Lieutenant General John Forbes ' Portuguese contingent deployed on the extreme left at Arles - sur - Tech and Amelie - les - Bains - Palalda . Dugommier placed Augereau on his right flank with 6 , 400 infantry and 80 cavalry . Augereau ' s right brigade occupied Taillet , his centre brigade Oms , and his left brigade Llauro . Sauret ' s division of 7 , 300 infantry and 100 Hussars held the coastal sector on the left flank . Pérignon ' s centre division represented the main French striking force with 8 , 500 infantry and 1 , 300 cavalry , backed by three reserve brigades totalling 7 , 000 men . The French commander believed that the Spanish army ' s centre of gravity was too far west and planned to exploit this weakness . He hoped to cross the Tech and roll up the right flank of the Spanish centre division . To make this task easier , he directed Augereau to demonstrate in front of Céret and lure the Spanish into drawing more troops to their left flank . Pérignon held his troops back from the river to hide the true French intentions . The main Spanish communications ran from Le Boulou through the Pass of Le Perthus ( 300 meters altitude ) near the Fort de Bellegarde . Dugommier wanted to force the Army of Catalonia into a retreat over the much more difficult Col du Porteille ( 800 metres altitude ) , four km to the southwest of Le Perthus . If he could achieve this , the Spanish might have to abandon their wagons , cannons , and supplies . Baiting the trap . In late April , Augereau built a redoubt at the Saint Ferriol hermitage , north of Céret . De la Union countered by constructing two redoubts of his own . On 27 April , Augereau probed the Spanish positions , then retired . The following day , Augereau captured one of the new Spanish redoubts , prompting the Spanish army commander to order 2 , 000 troops under the Prince of Montforte from his center to his left . On 29 April , de la Union launched 3 , 000 troops , including cavalry led by General Pedro Mendinueta y Múzquiz , to attack Augereau on the north bank . Following his instructions , the French division commander fought a rear guard action , drawing the Spanish troops toward Oms . De la Union finally called off the attack , but he left Mendinueta ' s cavalry to observe Augereau . That night , the Spanish generals held a council of war . De la Union ' s chief of staff Tomàs Morla saw through Augereau ' s actions and proposed that Navarro ' s division attack on the right while de Vives and de las Amarilas joined forces and attacked the French centre near Le Boulou . The council voted to adopt this action , which would secure the supply road from Le Boulou to Bellegarde . As a precaution , the council decided to withdraw the army ' s trains by the road to Bellegarde . However , they decided there was plenty of time to issue orders the next morning , rather than that evening . French attack . In the early hours of 30 April , Pérignon ' s division crossed the Tech at the Brouilla ford , planning to climb the mountains behind the Spanish camps in order to take the defences in the rear . General of Brigade Dominique Martin ' s left flank brigade marched past Saint - Génis - des - Fontaines and began ascending Saint Christopher Peak . His men reached the hermitage where they emplaced six cannon and 13 howitzers to fire on the Spanish positions from the rear . Then part of his brigade advanced west to cut the road to Bellegarde . General of Brigade Théodore Chabert ' s brigade advanced on Villelongue - dels - Monts while General of Brigade François Point ' s right flank brigade began attacking the fortified camp at Montesquieu - des - Albères , defended by Colonel Francisco Javier Venegas . La Barre supported Point ' s troops , while Victor with a reserve brigade occupied Saint - Génis to keep Navarro ' s division sending help to the Spanish center . Two more reserve brigades under General of Brigade Louis Lemoine attacked Trompettes . While these battles were being fought in the centre , Augereau retook Oms from Mendinueta on the French right flank and Sauret captured Argelès - sur - Mer from Navarro on the left . In order to give an impression of French superiority , Dugommier arrayed a large body of poorly trained volunteers near his headquarters at Banyuls - dels - Aspres . De la Union sent Montforte with 2 , 800 infantry and 800 cavalry to reinforce the Camp of Trompettes and Del Puerto with 2 , 000 more to help Venegas . But neither of these forces were able to halt the concentrated French offensive . On 1 May , seeing his defences fatally compromised , de la Union made preparations to retreat . Montforte abandoned Trompettes and withdrew to the south bank across a ford near Le Boulou . That day , the French assault overran the camp at Montesquieu - des - Albères and the Spanish retreated , taking the badly wounded Venegas with them . La Barre sent General of Brigade François Jean Baptiste Quesnel with his brigade along the south bank to cut off the Spanish retreat , but this effort failed . On the western flank , Augereau sent troops under Generals of Brigade Jean Joseph Guieu and Guillaume Mirabel to push Mendinueta ' s cavalry back to Céret . Chased by Quesnel ' s cavalry , Montforte retreated south on the road to Bellegarde . But at Les Cluses he ran into an ambush set by Martin ' s brigade . In a scene of chaos , a part of the Spanish wagon and artillery trains were wrecked or abandoned . The bulk of the Spanish army headed for Maureillas - las - Illas before climbing the steep road to the Col du Porteille . After covering the withdrawal at Céret , de Vives pulled out of the town and Augereau crossed the bridge to harass the Spanish retreat . The Portuguese division withdrew across a pass farther west . Results . The Spanish army suffered 2 , 000 killed and wounded . An additional 1 , 500 soldiers , 140 guns , and all of the army trains and baggage fell into French hands . French losses are given as 20 killed and 300 wounded . Historian Digby Smith stated . " The Spanish army never recovered from this setback . " After Boulou , the only Spanish forts on French soil were Collioure and Bellegarde . The French captured the first on 26 May while Bellegarde held out until 17 September 1794 .