Douro (Peninsular War).
Fought May 12, 1809, when 12,000 British under Wellesley (the Duke of Wellington) crossed the Douro and drove the French under Soult out of Oporto. The French numbered about 24,000, of whom 5,000 were killed, wounded or captured, mainly during the pursuit. In the action itself, the French lost 500, the British, 116.