After the discoveries of Christopher Columbus (1451-1506), Pope Alexander VI (1431-1503) issued the bull Inter Caetera in May 1493, assigning to the Spanish crown all the lands discovered west of a meridian set at 100 leagues from the Cape Verde Islands. The lands to the east of the line would remain in the possession of Portugal, which, however, felt unfairly treated by the Papal bull. King John II of Portugal (1455-1495) accordingly started talks with Ferdinand II of Aragon (1452-1516) to reach a more equitable agreement, pointing out that the meridian set by the Pope would have curbed Spanish control in Asia. On June 7, 1494, at Tordesillas, in Castile, the two monarchs signed the treaty that divided the world outside Europe into two large empires ruled by Spain and Portugal. The meridian marking the boundary was shifted to 370 leagues (1,770 km) west of the Cape Verde Islands, or longitude 46°37' west.