Brazilian border
Brazil Beyond Tordesillas: The Portuguese Crossed a Line That Was on the Map… and Changed the Map
In 1494, Portugal and Spain did something extraordinary. They sat down to negotiate and drew an imaginary line across the world. On one side would lie the territories belonging to Spain. On the other, those belonging to Portugal.
The agreement was called the Treaty of Tordesillas. But there was a small problem: the map said one thing, and the explorers were about to do another.
A Line No One Could See
At that time, Europeans still did not fully know the size or shape of South America. The Tordesillas line was drawn long before Portugal and Spain had completely explored the continent.
On paper, it seemed simple. But in reality, there were enormous jungles, rivers, mountains, and unknown territories. And the further the Portuguese advanced into the interior of South America, the more evident it became that that imaginary line was not going to stop them.
The Bandeirantes
Over the following centuries, groups of Portuguese explorers, settlers, and expeditionaries known as bandeirantes ventured further and further inland. They set out mainly from São Paulo and traveled enormous distances.
They crossed forests, forded rivers, and explored territories that were far from the coastal areas initially occupied by Portugal. Some sought riches. Others sought Indigenous people to enslave. They also took part in the search for gold and precious stones and in the exploration of new lands.
And each expedition meant the Portuguese came to know and occupy territories increasingly farther from the Atlantic.
The Map Begins to Feel Too Small
Here is where things get truly interesting. The Tordesillas line still existed in the documents, but the Portuguese were already far beyond it. In practice, Portugal had extended its presence across enormous regions of South America’s interior.
Spain also had its own territories and expeditions, but controlling a territory on paper was very different from actually occupying it.
And in an era when maps still had vast unknown spaces, whoever explored, founded settlements, and established a presence could end up changing the border. Reality was beginning to reshape the map.
And What Did Spain Do?
For a long time, Portugal and Spain had to confront a complicated question: Where should the border really be? Pointing to the old Tordesillas line was no longer enough. The territories that Portugal had occupied and explored had to be taken into account.
That is why both countries began negotiating new agreements. The most important one was the Treaty of Madrid of 1750.
A New Map
The Treaty of Madrid largely abandoned the old idea of dividing America by an imaginary line. Instead, a much more practical principle was used: the border had to take into account who actually occupied each territory.
Portugal retained large areas that lay west of the old Tordesillas line. In exchange, it also had to make concessions in other areas. The result was a massive transformation of South America’s borders.
From the Old Map to Present-Day Brazil
Subsequent agreements between Portugal and Spain continued to modify the borders. Gradually, the Portuguese territory in South America took on a shape much more similar to that of present-day Brazil.
The old Tordesillas line was left behind. And a territory that initially seemed destined to occupy a relatively limited part of South America ended up becoming the largest country on the continent.
When Walking Changes a Map
Brazil’s history demonstrates something very important about maps: sometimes we think borders are permanent lines that have always been where we see them today. But many have changed over time due to explorations, wars, treaties, and the occupation of new territories.
In this case, an imaginary line drawn in Europe ended up colliding with a vast and unknown reality on the other side of the ocean. The Portuguese kept pushing westward. And when it came time to redraw the borders, the map had to adapt to reality.
It Changed the Maps
“Brazil Beyond Tordesillas” belongs to the It Changed the Maps category because it tells how a line drawn on a map in 1494 ended up being insufficient to explain what was happening in South America. First there was a line. Then came the explorers. Then new occupied territories appeared. And finally, Portugal and Spain had to sit down again to draw the borders in a different way.
What happens when someone decides that a line drawn on a map is not going to stop them from moving forward? In Brazil’s case, the answer was simple: the map changed.
