The reign of Pedro was not without note, also, in foreign affairs. Even before settling his dispute with the Union he had accomplished something for the aggrandizement of Aragon. He somewhat treacherously provoked a quarrel with the king of Majorca, and then conquered the island in 1343. Proceeding at once against the same king’s possessions in southern France he incorporated them into his kingdom. Pedro had also assisted Alfonso XI of Castile against the Benimerines, contributing to the victory of the Salado in 1340. The war with Genoa and the uprisings in Sardinia which had filled the reign of his predecessor gave trouble also to Pedro, but after a campaign in Sardinia in person he was able temporarily to get the upper hand. His intervention in the civil wars of Castile has already been noted, and from these he came out with some not greatly important advantages. He also cast his eyes upon Sicily with a view to restoring it to the direct authority of the Aragonese crown, although this was not accomplished in his reign, and he encouraged commercial relations with the lands of the eastern Mediterranean. In 1381 he accepted an offer to become the sovereign of the Catalan duchy of Athens. These events were more indicative of a conscious Catalan policy of predominance in the Mediterranean than important in themselves. [Sidenote: Juan I and Martín I.] [Sidenote: The dispute over the succession and the crowning of Ferdinand I.] The reigns of the next two kings, Juan I (1387-1395) and Martín I (1395-1410), were more important from the standpoint of social institutions than in external political events. In the former reign occurred the loss of the duchy of Athens. In the latter, the island of Sicily, as foreseen by Pedro IV, returned to the Aragonese line when Martín of Sicily succeeded his father as king of Aragon. On the death of Martín without issue, a dispute arose as to the succession to the throne. The most prominent claimants were Ferdinand of Antequera, then regent of Castile, a son of Martín’s sister, and Jaime, count of Urgel, son of a cousin of Martín. Ferdinand was supported by the Aragonese anti-pope, Benedict XIII,[33] by the ecclesiastical and popular elements of most of Aragon proper, by various nobles, and by the political influence of the Castilian state, while Jaime counted on the popular support of Catalonia and Valencia and of part of Aragon, as well as on various noble families. Jaime had the advantage of being a native of the kingdom, while Ferdinand was looked upon as a foreigner, but as a matter of law Ferdinand had the better claim. For two years there were serious disturbances on the part of the noble families, which united their personal rivalries to the question of the dynastic succession. Finally, the matter was left to a commission of nine, three each from Aragon, Catalonia, and Valencia, and this body rendered a decision, in 1412, in favor of the Castilian claimant, who thereby became Ferdinand I