When Columbus first returned to Spain, the Portuguese claimed that he had merely
visited a part of their dominion of Guinea in Africa. Spain and Portugal accordingly asked Pope Alexander VI to settle the dispute. He complied by drawing a north-south Line of Demarcation in 1493.

If Spain discovered lands west of this line, the Spanish king was to have them if they were not already owned by a Christian ruler. In 1494 the line was drawn through a point 370 leagues west of the Cape Verde Islands.
In 1500 a Portuguese mariner, Pedro Alvarez Cabral, sailing along Africa en route to India, was carried by a storm to Brazil. He claimed the land for Portugal since it lay east of the line. When the Portuguese king heard of
Cabral's discovery, he sent out an expedition which sailed hundreds of miles along the South American coast.