Sancho IV of Navarre was a king who ruled from 1425 to 1479. He was a member of the House of Évreux and played a significant role in the political landscape of Navarre. His reign was marked by efforts to strengthen the kingdom and maintain its independence amid the pressures from neighboring powers. During his rule, Sancho IV faced challenges, including conflicts with the Crown of Castile and internal disputes. He worked to consolidate his authority and improve the administration of his kingdom. His leadership contributed to the cultural and political development of Navarre during the late medieval period.