<P> Initially, the line of demarcation did not encircle the Earth . Instead, Spain and Portugal could conquer any new lands they were the first to discover, Spain to the west and Portugal to the east, even if they passed each other on the other side of the globe . But Portugal's discovery of the highly valued Moluccas in 1512 caused Spain to argue in 1518 that the Treaty of Tordesillas divided the Earth into two equal hemispheres . After the surviving ships of Magellan's fleet visited the Moluccas in 1521, Spain claimed that those islands were within its western hemisphere . In 1523, the Treaty of Vitoria called for the Badajoz Junta to meet in 1524, at which the two countries tried to reach an agreement on the anti-meridian but failed . They finally agreed in a treaty signed at Zaragoza that Spain would relinquish its claims to the Moluccas upon the payment of 350,000 ducats (≈ 100 kg) of gold by Portugal to Spain . To prevent Spain from encroaching upon Portugal's Moluccas, the anti-meridian was to be 297.5 leagues or 17 ° to the east of the Moluccas, passing through the islands of Las Velas and Santo Thome . This distance is slightly smaller than the 300 leagues determined by Magellan as the westward distance from los Ladrones to the Philippine island of Samar, which is just west of due north of the Moluccas . </P> <P> The Moluccas are a group of islands west of New Guinea . However, unlike the large modern Indonesian archipelago of the Maluku Islands, to 16th - century Europeans the Moluccas were a small chain of islands, the only place on Earth where cloves grew, just west of the large north Malukan island of Halmahera (called Gilolo at the time). Cloves were so prized by Europeans for their medicinal uses that they were worth their weight in gold . 16th - and 17th - century maps and descriptions indicate that the main islands were Ternate, Tidore, Moti, Makian and Bacan, although the last was often ignored even though it was by far the largest island . The principal island was Ternate at the chain's northern end (0 ° 47'N, only 11 kilometres (7 mi) in diameter) on whose southwest coast the Portuguese built a stone fort (Forte de São João Baptista de Ternate) during 1522--23, which could only be repaired, not modified, according to the Treaty of Saragossa . This north - south chain occupies two degrees of latitude bisected by the equator at about 127 ° 24'E, with Ternate, Tidore, Moti, and Makian north of the equator and Bacan south of it . </P> <P> Although the treaty's Santo Thome island has not been identified, its "Islas de las Velas" (Islands of the Sails) appear in a 1585 Spanish history of China, on the 1594 world map of Petrus Plancius, on an anonymous map of the Moluccas in the 1598 London edition of Linschoten, and on the 1607 world map of Petro Kærio, identified as a north - south chain of islands in the northwest Pacific, which were also called the "Islas de los Ladrones" (Islands of the Thieves) during that period . Their name was changed by Spain in 1667 to "Islas de las Marianas" (Mariana Islands), which include Guam at their southern end . Guam's longitude of 144 ° 45'E is east of the Moluccas' longitude of 127 ° 24'E by 17 ° 21', which is remarkably close by 16th - century standards to the treaty's 17 ° east . This longitude passes through the eastern end of the main north Japanese island of Hokkaidō and through the eastern end of New Guinea, which is where Frédéric Durand placed the demarcation line . Moriarty and Keistman placed the demarcation line at 147 ° E by measuring 16.4 ° east from the western end of New Guinea (or 17 ° east of 130 ° E). Despite the treaty's clear statement that the demarcation line passes 17 ° east of the Moluccas, some sources place the line just east of the Moluccas . </P> <P> The Treaty of Saragossa did not modify or clarify the line of demarcation in the Treaty of Tordesillas, nor did it validate Spain's claim to equal hemispheres (180 ° each), so the two lines divided the Earth into unequal hemispheres . Portugal's portion was roughly 191 ° whereas Spain's portion was roughly 169 ° . Both portions have a large uncertainty of ± 4 ° because of the wide variation in the opinions regarding the location of the Tordesillas line . </P>

The treaty of tordesillas divided south america between spain and portugal