A rivalry developed between Spain and Portugal over the exploration of the seas. When King Ferdinand and Queen Isabella of Spain heard of King Manuel's plans to send ships west to claim for Brazil, they asked him to wait until it was decided to whom the seas and conquests belonged.
In 1493, Pope Alexander VI established the Treaty of Tordesillas, which divided the world in two. Portugal could claim lands East of the Line of Demarcation, and Spain could claim lands West of the line.
