<P> The war now fell into a temporary lull, with the superior French unable to find an advantage and coming under increasing pressure from Spanish guerrillas . The French had over 350,000 soldiers in L'Armée de l'Espagne, but over 200,000 were deployed to protect the French lines of supply, rather than as substantial fighting units . </P> <P> Wellington renewed the allied advance into Spain in early 1812, besieging and capturing the border fortress town of Ciudad Rodrigo by assault on 19 January and opening up the northern invasion corridor from Portugal into Spain . This also allowed Wellington to proceed to move to capture the southern fortress town of Badajoz, which would prove to be one of the bloodiest siege assaults of the Napoleonic Wars . The town was stormed on 6 April, after a constant artillery barrage had breached the curtain wall in three places . Tenaciously defended, the final assault and the earlier skirmishes left the allies with some 4,800 casualties . These losses appalled Wellington who said of his troops in a letter, "I greatly hope that I shall never again be the instrument of putting them to such a test as that to which they were put last night ." The victorious troops massacred about 4,000 Spanish civilians . </P> <P> The allied army subsequently took Salamanca on 17 June, just as Marshal Marmont approached . The two forces met on 22 July, after weeks of maneuver, when Wellington soundly defeated the French at the Battle of Salamanca, during which Marmont was wounded . The battle established Wellington as an offensive general and it was said that he "defeated an army of 40,000 men in 40 minutes ." The Battle of Salamanca was a damaging defeat for the French in Spain, and while they regrouped, Anglo - Portuguese forces moved on Madrid, which surrendered on 14 August . 20,000 muskets, 180 cannon and two French Imperial Eagles were captured . </P> <P> After the allied victory at Salamanca on 22 July 1812, King Joseph Bonaparte abandoned Madrid on 11 August . Because Suchet had a secure base at Valencia, Joseph and Marshal Jean - Baptiste Jourdan retreated there . Soult, realising he would soon be cut off from his supplies, ordered a retreat from Cádiz set for 24 August; the French were forced to end the two - and - a-half - year - long siege . After a long artillery barrage, the French placed together the muzzles of over 600 cannons to render them unusable to the Spanish and British . Although the cannons were useless, the Allied forces captured 30 gunboats and a large quantity of stores . The French were forced to abandon Andalusia for fear of being cut off by the allied armies . Marshals Suchet and Soult joined Joseph and Jourdan at Valencia . Spanish armies defeated the French garrisons at Astorga and Guadalajara . </P>

When did the war between france and spain reach a turning point