The Battle of the Black Mountain was fought from 17 to 20 November 1794 between the army of the First French Republic and the allied armies of the Kingdom of Spain and the Kingdom of Portugal. The French, led by Jacques François Dugommier defeated the Allies, who were commanded by Luis Firmín de Carvajal, Conde de la Unión. Though the Spanish right wing held, its left flank was driven back on the first day's fighting. On the last day of the battle, the French overran a key position and put the Spanish army to rout.