Tordesillas Divides Overseas Claims Between Two Crowns

In June 1494, representatives of the Kingdom of Portugal and the Crown of Castile gathered in the Castilian town of Tordesillas to resolve escalating territorial rivalry in the Atlantic Ocean. Following Christopher Columbus's return to Europe in 1493 from lands claimed for Castile, King John II of Portugal asserted that these voyages infringed upon Portuguese rights established by earlier treaties and papal declarations. Pope Alexander VI responded with bulls that granted Castile control over regions west of a meridian set 100 leagues beyond the Azores or Cape Verde islands. Dissatisfied because this papal division excluded Portuguese navigation toward India around southern Africa, John II negotiated directly with King Ferdinand and Queen Isabella to shift the boundary substantially farther west.

The resulting Treaty of Tordesillas, signed on 7 June 1494 and later ratified by both monarchies and Pope Julius II, established a line of demarcation 370 leagues west of the Cape Verde islands. Lands to the east were allocated to Portugal, while territory to the west fell to Castile. This compromise protected Portuguese sea routes down the African coast and inadvertently secured for Portugal a future foothold in the Americas, where Pedro Alvares Cabral made landfall in 1500 in what is now eastern Brazil. Castile retained claims to vast continental reaches across the Americas, asserting dominion over territories inhabited by indigenous societies who neither knew of the agreement nor accepted its authority.