Key Facts
- Duration
- 14 April – 10 May 1811 (26 days)
- Anglo-Allied force size
- ~13,000 soldiers
- French commander
- General Antoine François Brenier de Montmorand
- Distance from Lisbon
- ~300 km northeast
- Prior capture of Almeida
- Siege of Almeida, 1810
Strategic Narrative Overview
Anglo-Allied forces numbering approximately 13,000 men under Generals Sir Alexander Campbell and Sir William Erskine encircled the French garrison beginning 14 April 1811. A French relief attempt was mounted but ultimately failed to break the siege. With no prospect of external rescue, French commander Brenier devised a night breakout plan, first blowing up sections of the Almeida fortress to deny its use to the besieging forces before leading his troops through Allied lines under cover of darkness.
01 / The Origins
Almeida, a fortified border town in northeastern Portugal, had been captured from a Portuguese garrison during the 1810 Siege of Almeida, placing a French garrison inside its walls. As the broader Peninsular War shifted momentum toward the Anglo-Allied forces under Wellington, the French garrison at Almeida became isolated and surrounded by a significantly larger British force in April 1811, prompted by the failure of French efforts to maintain supply lines and relieve isolated garrisons.
03 / The Outcome
Despite being surrounded by a far superior force, Brenier's garrison successfully escaped on the night of 10 May 1811, largely intact. Wellington was furious at the failure to intercept the French, attributing the outcome to poor coordination among British commanders, particularly Erskine. The fortress was left in ruins after the explosions, and the escaped French troops rejoined their army, depriving the Allies of a decisive capture that should have been within reach.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Antoine François Brenier de Montmorand.
Side B
1 belligerent
Sir Alexander Campbell, 1st Baronet, Sir William Erskine, 2nd Baronet, Arthur Wellesley, Viscount Wellington.
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.