Treaty of Tordesillas (1494)

Shortly after Columbus arrival from the "West Indies", a division of influence became necessary to avoid conflict between Spanish and Portuguese. On 4 May 1493, two months after Columbus arrival, the Catholic Monarchs got a bull (Inter caetera) from Pope Alexander VI stating that all lands west and south of a pole-to-pole line 100 leagues west and south of the Azores or the Cape Verde Islands should belong to Spain and, later, all mainlands and islands then belonging to India. It did not mention Portugal, which could not claim newly discovered lands east of the line.

King John II of Portugal was not pleased with the arrangement, feeling that it gave him far too little land—preventing him from reaching India, his main goal. He then negotiated directly with King Ferdinand and Queen Isabella of Spain to move the line west, allowing him to claim newly discovered lands east of it.

An agreement was reached in 1494, with the Treaty of Tordesillas that "divided" the world between the two powers. In this treaty the Portuguese "received" everything outside of Europe east of a line that ran 270 leagues west of the Cape Verde islands (already Portuguese), and the islands discovered by Christopher Columbus on his first voyage (claimed for Spain), named in the treaty as Cipangu and Antilia (Cuba and Hispaniola), this gave them control over Africa, Asia and eastern South America (Brazil). The Spanish received everything west of this line, territory that was still almost completely unknown, and proved to be mostly the western part of the American continent plus the Pacific Ocean islands.