Alfonso VIII of Castile

Alfonso VIII took the throne of Castile in 1158 at age two and held it until his death in 1214. In 1195 his army was crushed by the Almohads at Alarcos, a disaster that could have ended Castilian expansion. Instead he spent the next seventeen years building a coalition of Christian princes and foreign crusaders, then led them to victory at Las Navas de Tolosa in 1212 — the battle that shattered Almohad dominance and tipped the peninsula toward Christian control. His reign also saw Castile eclipse León and, through alliance with Aragon, pull the two major Christian kingdoms into lasting alignme…