Queen regnant
Upon the death of her mother in November 1504, Joanna became Queen regnant of Castile and her husband "jure uxoris" its king in 1506. Joanna's father, Ferdinand II, lost his monarchical status in Castile although his wife's will permitted him to govern in Joanna's absence or, if Joanna was unwilling to rule herself, until Joanna's heir reached the age of 20.