Campaign of Gipuzkoa The Campaign of Gipuzkoa was part of the Spanish Civil War , where the Nationalist Army conquered the northern province of Gipuzkoa , held by the Republic . Background . In late July Mola´s troops suffered a shortage of ammunition ( having only 26 , 000 rounds of ammunition ) . Then Francisco Franco sent him large supplies of ammunition and weapons from Italy and Germany via Portugal ( 600 , 000 rounds ) . On August 13 , Mola met Franco in Seville and decided to capture San Sebastián and Irún in order to cut the Basques off from the French Border at the western end of the Pyrenees . The campaign . Advance on San Sebastian . The campaign was initially conceived by General Emilio Mola as an advance to Irún , to cut the northern provinces off from France , and to link up with the Nationalist garrison in San Sebastián that was to have seized that city . The campaign was diverted from the advance on Irún when the direct route to the town was blocked by the demolition of the bridge at Endarlatsa . When word came that the Nationalists in San Sebastián were besieged in the Cuartel de Loyola , Alfonso Beorlegui diverted all his forces westward toward that town in an attempt to relieve the Nationalist garrison . Two other Nationalist columns advanced on the city from points further west with the intent of cutting it off from Vizcaya . Nevertheless on 27 July , the Nationalist garrison in San Sebastián surrendered . Advance on Irun . Following the failure to relieve the siege of the Nationalists in San Sebastian , the forces of Beorlegui resumed their advance on Irún and cut off the northern provinces of Gipuzkoa , Biscay , Santander and Asturias , from their source of arms and support in France by taking that city . On August 11 the Nationalist took Tolosa and Beorlegi seized Picoqueta , a key ridge commanding the approach to Irún . Telesforo Monzon , a Basque Nationalist , travelled to Barcelona to seek aid , but he only got 1 , 000 rifles , and the basque nationalist confiscated the gold in the local branch of the Bank of Spain to buy weapons in France , but on August 8 the French government closed the frontier . On August 17 , the rebel battleship " España " , the cruiser " Almirante Cervera " and the destroyer " Velasco " arrived at San Sebastián and started to shell the city . After that Ju - 52 bombers started to bomb Irún and San Sebastián . Furthermore , the Nationalists captured the republican commander in Guipuzcoa , Pérez Garmendia . Fall of Irun and San Sebastián . On August 26 , Beorlegi began the assault on Irún and after bloody combats he occupied the town on September 3 , but he was wounded and died soon after . Retreating anarchists burned the city . The Nationalists followed this up with the capture of San Sebastián on September 13 , and an advance to the border of Vizcaya . There , the resistance of the northern provincial forces and the exhaustion of the Nationalists resulted in an end of the offensive until the War in the North began . Aftermath . The Nationalist conquered 1 , 000 square miles of terrain and many factories . Furthermore , they cut loss the Basques from the friendly France . Then , Indalecio Prieto , the Republican minister of defense sent the Republican fleet to the northern ports in order to prevent a rebel blockade .