Bermudo III of León

Bermudo III (c. 1015–1037), son of Alfonso V of León and Elvira Menéndez, became king of León as a child in 1028 and was the last ruler of the line of Peter of Cantabria.

In 1034 Sancho III of Pamplona drove him from his kingdom and he fled to Galicia. He recovered León, but on 4 September 1037 he was defeated and killed at the Battle of Tamarón fighting his brother-in-law Ferdinand of Castile, who then annexed the kingdom.