At first glance, Tordesillas, a small city on the banks of the Duero River in the Valladolid Province of Spain, seems perfectly ordinary. It has an old quarter with a well-preserved Plaza Mayor and churches that date back to medieval times. But mention it in São Paulo, Cartagena, or any other Central or South American city and many will immediately recognise its name. It was here in 1494 that Spain (then the Kingdom of Castile) and Portugal divided lands they had yet to find – and thus set the stage for Brazil to become the only Portuguese-speaking country in the Americas.
The town’s location was probably what made it the perfect seat for the negotiations of the historic Treaty of Tordesillas. “It [was at the] crossroads of a knot of roads [that were] very important,” said Miguel Angel Zalama, professor of Art History at the University of Valladolid and the Director of Tordesillas Center of Ibero-American Relations. “There was [also] a palace [and] everything indicates that [the treaty] was signed there.”
But the presence of royal quarters and the town’s geographical advantage may not have been the only reasons that the Catholic monarchs, Isabella of Castile and Ferdinand of Aragon, chose it.
“With the title of ‘very illustrious, ancient, crowned, loyal and noble villa’ [given in the Middle Ages], this Castilian town was linked by historical tradition to Portugal,” explained Ricardo Piqueras Céspedes, professor of History at the University of Barcelona. “In the 14th Century, Queen Mary of Portugal and [then] infant Beatriz of Portugal lived there. It’s possible this was a political gesture so that the Portuguese were more comfortable on a kind of neutral ground.”
Isabella and Ferdinand had good reason to appease Portugal. Although deliberated during May and June 1494, the Treaty of Tordesillas was a year-long process replete with uncertainty, with the high potential of war between two countries and Spain’s anxiety over its role in the Atlantic conquests. The road to negotiating the treaty began when, on return from his maiden voyage to what he thought was India, explorer Christopher Columbus ran into a storm. He had to throw anchor near Lisbon, and although his voyage was sponsored by Spanish monarchs Ferdinand II and Isabella I, he was forced to share the news of his discoveries first with John II, the King of Portugal. Convinced that the new islands fell under the 1479 Treaty of Alcáçovas-Toledo, which gave lands south of the Canary Islands to Portugal, John II declared them his dominion.
Meanwhile, Martin Alonso Pinzón, the Spanish navigator who accompanied Colón, managed to bring his boat, the Pinta, ashore in Spain, and immediately sent word of newly found lands to Barcelona where the Catholic monarchs were holding court while Ferdinand recovered from a wound. Acting on that information, the monarchs dispatched their emissaries to Pope Alexander VI with a claim on Colón’s discoveries. Originally from Valencia (then part of the Kingdom of Aragon) and thus partial to the interests of the Catholic monarchs, the pope issued three new Papal bulls. One of them – the 4 May 1493 Inter Caetera– effectively cancelled the Treaty of Alcáçovas-Toledo. Instead of the parallel, which per that treaty divided the Atlantic between Portugal and Spain along a horizontal line, a vertical demarcation border was drawn from pole to pole across the Atlantic Ocean.
The Portuguese were incensed. In addition to losing the new islands, they now had no room to manoeuver when embarking on their voyages to Africa as the line ran only 100 leagues (about 320 miles) west of Cape Verde.
“The Portuguese wanted to preserve their colonies in Africa [and] their islands in the Atlantic,” Zalama said. “The line was a shock because they couldn’t navigate at all. To navigate [they] needed favorable winds and to have those winds it was sometimes necessary to make a great circle. With this bull they couldn’t because [they would have found themselves] in Castilian territory.”
A flurry of diplomatic exchanges followed between Portugal and Spain. Neither side wanted a war, yet both organised and maintained armadas during the talks. In the midst of discussions in September 1493, Colón left on his second voyage promising his sovereigns information to help with negotiations. He delivered on this vow in April 1494 when he sent back a map of his discoveries. But because he didn’t know whether John II had agreed to forego the horizontal division, he doctored the map. He lifted the latitude of Hispaniola (now Haiti/the Dominican Republic) – the island his expedition encountered on the first voyage – north several degrees, placing it on the same parallel as the Canary Islands, and thus ensuring the Spanish dominion as per the Alcáçovas-Toledo Treaty.
But by the time Colón’s map arrived, the Portuguese had already conceded to the vertical partition. Mostly concerned with being able to sail to Africa, John II only requested the line to be moved to 370 leagues (1,185 miles) west of Cape Verde. Under that agreement Portugal would get everything to the east of the line – the already known Cape Verde Islands and the African coast – while Spain’s territory would extend west of it and include Colón’s recent finds. Because Colón’s new map didn’t show any new lands on the Portuguese side of the demarcation, Isabella and Ferdinand agreed.
None of them knew yet that the new line crossed the tip of Brazil, and, thus placed the eastern coast of that country within the dominion of Portugal. In 1500, the Portuguese navigator Pedro Álvares Cabral encountered it on his voyage and claimed it for his king. In the centuries that followed, Portugal expanded its influence inland and Brazil became the only Portuguese-speaking nation on the American continent.
“For the vast majority of the Brazilian people [today], the Treaty of Tordesillas means a declaration that the Portuguese crown could take possession of the ‘unknown’ West lands,” said Ana Paula Torres Megiani, professor of Iberian History at the University of São Paulo. “[But it’s also] a key historical moment to understand the relations of domination and hegemony between Europe and the world.”
CORRECTION: A previous version of this article said Christopher Columbus was Spanish. He was born in Genoa, Italy.
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