Joanna of Castile, also known as la Beltraneja, lived a tumultuous life filled with political strife, disputed claims to the throne, and complex alliances. Born on February 28, 1462, at the Royal Alcazar of Madrid, Joanna's parentage was marred by controversy and rumors. Her father, King Henry IV of Castile, was rumored to be impotent, leading to doubts about Joanna's legitimacy. Detractors suggested that she was the child of Beltrán de la Cueva, a royal favorite at court, and thus nicknamed her "la Beltraneja."