Alfonso I, 1109?–1185, first king of Portugal, son of Henry of Burgundy. After his father's death (1112), his mother, Countess Teresa, ruled the county of Portugal with the help of her Spanish lover, Fernando Pérez. In 1128 young Alfonso, who had allied himself with discontented nobles, defeated her in battle and drove her into León with Pérez (Alfonso did not, despite the popular legend, put her in chains at Guimarães). Beginning as little more than a quasi-independent guerrilla chief, Alfonso spent his life in almost ceaseless fighting against the kings of León and Castile and against the Moors to increase his prestige and his territories. In 1139 he defeated the Moors in the battle of Ourique (fought not at Ourique, but at some undetermined place). In 1147 he took Santarém by surprise attack and, with the help of the English, Flemish, and German crusaders, captured Lisbon. He began to style himself king in 1139, and in 1143, by the Treaty of Zamora, he placed his lands under papal protection and secured Castilian recognition of his title, which was confirmed (1179) by Pope Alexander III. Alfonso's son Sancho I ascended an established throne.
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