ALFONSO X., surnamed " the astronomer," "the philosopher," or " the wise" (el wthio), king of Leon and Castile, b. 1221, succeeded his father, Ferdinand III., in 1252. As early as the storming of Seville in 1248, he had given indications of his courageous spirit. But, instead of wisely attempting to expel the Moors and subdue the nobility, he lavished the resources of his kingdom in fruitless efforts to secure his election to the imperial throne of Germany. Rudolph of Hapsburg was chosen in opposition to him. Nor would pope Gregory X. recognize his claims even to the duchy of Swabia. Soon after, his throne was threatened by the turbulence of the nobility and his wars with the Moors. The latter, however, he defeated in 1263, in a bloody battle, and took from them Xeres, Medina-Sidonia, San-Lucar, and a part of Algarve, uniting at the same time Murcia with Castile. In 1271, an insurrection broke out in his dominions, at the head of which was his son Philip. Three years elapsed before it was finally quelled In the mildness with which he treated the rebels, men saw only indications of his weakness. But afterwards determining to employ more stringent measures, his son Sancho also rebelled, and in 1282 deprived him of his throne. He now sought the help of the Moors, but after fruitless efforts to recover his power, he died at Seville, April 4, 1284. He was the most learned
prince of his time, and has acquired lasting fame through the completion of the code of laws commenced (though this is disputed) by his father, and called Leyos de las Partidas, which in 1501 became the universal law of the land. There are still extant several long poems of his, besides a work on chemistry, and another on 'philosophy. He is also cred ited with a history of the church and of the crusades, and is said to have ordered a trans lation of the Bible into Spanish. He labored much to revive knowledge. increasing both the privileges and professorships of the university of Salamanca. He sought to improve the Ptolemaic planetary tables, whose anomalies had struck observers even at that early time. For this purpose, in 1210, he assembled at Toledo upwards of 50 of the most celebrated astronomers of that age. His improved tables, still known under the name of the Alfonsine tables, were completed in 1252 at the cost of 40,000 ducats—an unprecedented sum to be expended on such a work in those days. The results obtained by means of the Alfonsine tables were no more accur ate than those of the older ones, for both were based on the same erroneous hypothesis of Epicycles (q.v.). The Opusculos Legaks of A. were published by the royal historical society of Madrid in 1836.