the third king of Portugal (1211–23), under whom the reconquest of the south from the Muslims was continued.

Afonso II was the son of King Sancho I and Queen Dulcia, daughter of Ramón Berenguer IV of Barcelona. His obesity seems to have been caused by illness in his youth, and he was unable to lead his forces. However, they distinguished themselves in the victory of Alfonso VIII of Castile at Las Navas de Tolosa (1212). This marked the decline of the Muslim Almohads, and Afonso II's army seized Alcacer do Sal in 1217.

Afonso II instituted inquiries into land titles, challenging the church and other landowners. This led to a long conflict with nobles and churchmen, and in 1219 the archbishop of Braga excommunicated king and court and placed the kingdom under an interdict. These actions were confirmed by the papacy, but Afonso resisted until his death. He was succeeded by his son, Sancho II.