In 1063, Ferdinand I of Castile divided his realm among his sons, and the Kingdom of Galicia was granted to Garcia II of Galicia. In 1072, it was forcibly annexed by Garcia's brother Alfonso VI of León; from that time Galicia was united with the Kingdom of León under the same monarchs. In the 13th century Alfonso X of Castile standardized the Castilian language and made it the language of court and government. Nevertheless, in his Kingdom of Galicia the Galician language was the only language spoken, and the most used in government and legal uses, as well as in literature.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who standardized Castillan and made it the government's official language?
Alfonso X