 Joanna, born in 1462, was the only child born to King Henry IV of Castile and was called Princess of Asturias as heir presumptive to the throne.A rumour spread that she was not actually the daughter of King Henry but rather of Beltrán de la Cueva, the alleged lover of Henry's wife, Joan of Portugal.Joanna was thus nicknamed "la Beltraneja", as a mocking reference to her assumed father.