Alfonso X (also occasionally Alphonso X, Alphonse X, or Alfons X,[1] 23 November 1221 – 4 April 1284), called the Wise (Spanish: el Sabio), was the King of Castile, León and Galicia from 30 May 1252 until his death. During the Imperial election of 1257, a dissident faction chose him to be King of the Romans (Latin: Rex Romanorum; German: Römisch-deutscher König) on 1 April. He renounced his imperial claim in 1275, and in creating an alliance with England in 1254 his claim on Gascony also.(...) from http://es.wikipedia.org/wiki/Alfonso_X_de_Castilla acc. 05/01/2015