Sancho IV of Castile

Sancho IV of Castile (12 May 1258 – 25 April 1295) called the Brave (el Bravo), was the king of Castile, León and Galicia (now parts of Spain) from 1284 to his death. Following his brother Ferdinand's death, he gained the support of nobles who declared him king instead of Ferdinand's son Alfonso. Faced with revolts throughout his reign, before he died he made his wife regent for his son, who became Ferdinand IV.

Source: Wikipedia — https://en.wikipedia.org/wiki/Sancho_IV_of_Castile