Table of Contents / Explorers
Magellan Strait
Pacific Ocean
Spice Islands

Lines of Demarcation

On May 4, 1493, the Spanish-born Pope Alexander VI decreed in the bull Inter caetera that all lands west and south of a pole-to-pole line one hundred leagues west and south of any of the islands of the Azores or the Cape Verde Islands should belong to Spain. Portugal objected because its status and rights had been omitted and overlooked. King John II of Portugal began negotiations directly with King Ferdinand and Queen Isabella of Spain to push the line west and allow him to lay claim to lands discovered east of it. The result was the Treaty of Tordesillas.
            Signed in Tordesillas, Spain, on June 7, 1494, the treaty established a line of demarcation that was 370 leagues west of the Cape Verde Islands (already Portuguese). Spain gained most of the Americas, except for the Brazilian bulge of South America, and Portugal, whose explorers had already reached the west coast of Africa, could claim lands discovered to the east. However, because the line was neither defined by degrees of longitude nor strictly enforced, different interpretations regarding its practical implementation resulted. In addition, the line did not encircle the globe.

Lines of demarcation, 1493, 1494, and 1529. [From Wikipedia]

After Ferdinand Magellan’s expedition (1519–22), the area of the Pacific came into play, particularly the Spice Islands (Moluccas), which both countries claimed. Always needing money for his European wars, Charles V of Spain sought a practical solution to the “Moluccas issue” after he married Isabella of Portugal in 1526; he signed a new treaty with Portugal in Zaragoza, Spain, on April 22, 1529. The Treaty of Saragossa (or Zaragoza) provided an antimeridian to the line established by the Treaty of Tordesillas. Portugal paid Spain 350,000 ducats for the Moluccas, and, to prevent further Spanish encroachment, the new line of demarcation was established almost three hundred leagues (or 17°) to the east of these islands. Portugal got control of all of the lands to the west of the line, including Asia, and Spain received most of the Pacific Ocean. Spain’s argument that the Treaty of Tordesillas divided the world into two equal hemispheres was not recognized in the Treaty of Saragossa: Portugal’s share was approximately 191°, whereas Spain’s was roughly 169°, with a variation of about ±4° owing to the uncertainty of the location of the Tordesillas line. Spanish interest in the Philippines, shown by the new treaty to be on the Portugal side of the line, would become an issue in the later decades of the sixteenth century.
Table of Contents / Explorers
Magellan Strait
Pacific Ocean
Spice Islands