Bailén is probably the ancient Baecula, where the Romans, under Scipio the elder, signally defeated the Carthaginians in 209 and 206 B.C. In its neighbourhood, also, in 1212, was fought the great Battle of Las Navas de Tolosa, in which, according to the ancient chroniclers, the Castilians under Alphonso VIII, slew 200,000 Almohads, and themselves only lost 25 men. Although this estimate is absurd, the victory of the Christians was complete. There is a convent that dates from 729.