The siege of Olivenza of 11-22 January 1811 was an early success for the French during Marshal Soult’s invasion of Estremadura. Having split his army into two columns to cross the mountains between Andalusia and Estremadura, Soult had been forced to further split his force when he encountered a strong Spanish force under General Ballesteros that happened to be crossing the mountains in the opposite direction. As a result when Soult reached his destination, he was not strong enough to begin a siege of Badajoz, the original target of his expedition. Instead he turned south to deal with the minor fortress of Olivenza.
Olivenza had been Portuguese until the war of 1801, when it had been taken by siege. The breach made during that siege had only been partly repaired by 1811, the city only contained eighteen guns, of which eight were said to be serviceable during the siege, and the southern defences were dominated by a ruined lunette 300 yards south of the town. Before Soult began his invasion, the city was protected by one battalion of infantry, under the command of General Manuel Herck, an ailing Swiss soldier. When the French entered Estremadura, the Spanish commander in the area, General Mendizabal, posted 2,400 of his 6,000 infantry in Olivenza, and then retired to the north of Badajoz.
Marshal Soult's Invasion of Estremadura, 1811 Soult arrived outside Olivenza on 11 January at the head of Girard’s infantry division and one cavalry regiment. He was lacking siege guns, for they were still stuck in the mountains, but he did have Girard’s divisional guns, with which he began his siege. One battery was placed in the southern lunette, while two more batteries were placed opposite the old breach in the north west corner of the city. The light guns in the southern battery opened first on 12 January, while to the north the French began to dig regular parallels.
The first heavy guns arrived on 19 January, and opened fire on 22 January. The earth banks that had been used to block the old breach collapsed almost immediately, and the governor raised the white flag. On the next day 4,161 Spanish soldiers surrendered. Although the town’s defences were not strong, Herck’s performance was unimpressive – he had failed to make any attempts to interfere with the French siege works, despite having more than enough men to risk a sortie. The French lost 15 dead and 40 wounded, while the Spanish suffered 200 casualties during the siege. The Spanish resistance had not lasted for long enough for Soult’s missing infantry to return from chasing Ballesteros or for the siege train to come back together, but despite this Soult was still forced to begin his siege of Badajoz, arriving outside the city on 26 January. Olivenza would only remain in French hands for ten weeks, before falling to Beresford in a second short siege (9 April-15 April 1811).