Martin I King of Aragon died in Barcelona in 1410, his legitimate descendants, born of marriage with queen Maria, were already dead. Martin's second marriage, with Margarita of Aragon-Prades, did not produce any children. The important candidates for succession were:
Fadrique de Aragón y Luna (Frederick), Count of Luna, grandson of Martin I of Aragón and Queen María de Luna, bastard of their predeceased son of Martin the Younger King of Sicily, though legitimized by Antipope Benedict XIII.
Jaume, Count of Urgell, great-grandson of Alphoso IV of Aragon in the male line and appointed as Lieutenant of the Kingdom by Martin. Closest agnate, son of Martin's first cousin.
Alfons, Duke of Gandia, an octagenarian, grandson of Jaime II of Aragon in the male line, died in 1412 leaving his son as the next duke of Gandia. First cousin of Martin's father. The most senior (laterally as well as in age) and high in proximity to late reigning kings of Aragon (the stem of this succession).
Lluís III d'Anjou, Duke of Calabria, grandson of Juan I of Aragon through his mother Yolande of Aragon. Cognatic great-nephew of Martin. Heir general to the line, John I having been the eldest son of Peter IV of Aragon and elder brother of Martin.
Fernando de Trastámara, el de Antequera (Ferdinand), Infante of Castile, grandson of Peter IV through his mother Eleanor of Castille, queen of Castile. Cognatic nephew of Martin.
Louis III d'Anjou had the higher claim but in Caspe Fernando was elected King though.
WI Louis was proclaimed King in 1412? How is this altering History? Any thoughts?