When the campaigns in Africa were over, Afonso V found new grounds for battle in neighboring Castile. On December 11, 1474, King Henry IV of Castile died without a male heir, leaving just one daughter, Joanna. However, her paternity was questioned; it was rumored that his wife, Queen Joan of Portugal (Afonso's sister) had an affair with a nobleman named Beltrán de La Cueva. The death of Henry ignited a war of succession with one faction supporting Joanna and the other supporting Isabella, Henry's half-sister. Afonso V was persuaded to intervene on behalf of Joanna, his niece. He betrothed himself to her, proclaimed himself king of Castile and led troops into the kingdom. Because of their close blood-relationship, a formal marriage had to wait for papal dispensation.