Alfonso VI, 1643-83, king of Portugal (1656-83), son and successor of John IV. Slightly paralyzed and mentally defective, he led a dissolute youth until he came under the influence of the count of Castelho Melhor in 1662. The count of Castelho Melhor then took over the government and ruled ably. Under Castelho Melhor's direction the army won the series of victories over Spain (1663-65) that finally secured Spanish recognition of Portuguese independence (1668). After Alfonso's marriage (1666) to Marie Françoise of Savoy, daughter of the duc de Nemours, the young queen took a hand in government. She and the king's younger brother (later Peter II) fell in love, and in 1667 they forced Castelho Melhor from power and made Alfonso sign over the government to Peter, who became prince regent. A quick annulment of her marriage to Alfonso enabled Marie Françoise to wed the new regent. Alfonso was confined in the Azores until 1674 and at Sintra thereafter.

Alfonso VI, 1030-1109, Spanish king of León (1065-1109) and Castile (1072-1109). He inherited León from his father, Ferdinand I. Defeated by his brother Sancho II of Castile, he fled to the Moorish court of Toledo. After Sancho's assassination (1072) Alfonso succeeded to the throne of Castile and took Galicia from his brother García (1073). He thus became the most powerful Christian ruler in Spain. He encouraged Christians in Muslim lands to migrate north, and he raided Muslim territory, penetrating as far south as Tarifa. After the conquest of strategic Toledo (1085), he took many other cities and reached the line of the Tagus River. Alarmed by his advance, Abbad III (see Abbadids) and his Muslim allies called to their aid the Almoravid Yusuf ibn Tashfin, who defeated Alfonso in 1086. Alfonso was defeated again in 1108, and his only son died in the battle. Alfonso's reign gave a great crusading impulse to the reconquest of Spain and was also notable for the exploits of the Cid. Alfonso's court at Toledo became the center of cultural relations between Muslim and Christian Spain. French influence was strong because of the king's many French followers; French monks introduced the Cluniac reform into León during his reign. Alfonso was succeeded by his daughter Urraca.

known as Alfonso the Brave

(born before June 1040—died 1109, Toledo, Castile) King of León (1065–70) and of Castile and León (1072–1109). He inherited León from his father, Ferdinand I, and warred with his envious brother Sancho II. On Sancho's death he inherited Castile (1072); he also occupied Galicia and imprisoned his brother García, its rightful ruler. In 1077 Alfonso proclaimed himself emperor of all Spain. He took Toledo from the Muslims, but his demands for tribute led to the invasion of Spain by the North African Almoravids, and he was defeated at Zallaqah (1086). The Cid became an ally and defended eastern Spain, but Alfonso continued to lose ground against the Berber armies.

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