 The following dynasts are descendants, in the male line, of Urraca's first husband, Raymond of Burgundy.Following the death of Peter, a succession crisis arose between Peter's illegitimate half-brother Henry of Trastámara and the Englishman John of Gaunt, a great great grandson of Ferdinand III of Castile, who claimed the title of King of Castile and Léon by virtue of his marriage to Constance, daughter of Peter.Henry took the throne by force, and faced several military actions by John of Gaunt, who had forged an alliance with John I of Portugal in an attempt to enforce his claim, however John of Gaunt was unsuccessful in his campaigns, and Henry established the House of Trastámara as the new ruling dynasty of Castile.