October 7 – Alfonso VI becomes king of León and Castile, following the assassination of Sancho II. He is bestowed with the title of "Emperor of Spain", and is forced by El Cid (Rodrigo Diaz de Vivar), the standard-bearer of Sancho, to take an oath denying any involvement in his brother's death.
December 15 – Sultan Alp Arslan ("Heroic Lion") dies after a 9-year reign, during his campaign in Transoxiana. He is succeeded by his 17-year-old son Malik-Shah I, who is declared new ruler of the Seljuk Empire. Qavurt, a brother of Alp Arslan, claims the Seljuk throne for himself and occupies the capital of Isfahan.
China
Shen Kuo, Chinese polymathic scientist and statesman, is appointed as the head official for the Bureau of Astronomy – where he begins his work with the colleague Wei Pu on accurately plotting the orbital paths of the stars, planets, and moon three times a night for a continuum of five years.
Fall – Shen Kuo is sent to supervise Wang Anshi's program of surveying the buildup of silt deposits in the Grand Canal, outside the capital city of Kaifeng. Using an original technique, Shen successfully dredges the canal and demonstrates the formidable value of the silt gathered as a fertilizer.
