Ferdinand I of León was a king who ruled from 1037 to 1065. He was born around 1016 and became the first monarch to unite the kingdoms of León, Castile, and Galicia. His reign marked a significant period in the history of the Iberian Peninsula, as he expanded his territories and strengthened the Christian kingdoms against Muslim rule. Ferdinand I was known for his military campaigns and diplomatic skills. He was also a patron of the church, promoting the spread of Christianity. After his death, his kingdom was divided among his children, leading to the formation of separate kingdoms in the region.