Recently, while organizing Spanish historical materials, I discovered that many people’s understanding of the Treaty of Zaragoza is not very deep, particularly regarding the Treaty of Zaragoza’s longitude. This treaty, signed in 1529, actually had an extremely important impact on Spanish and Portuguese overseas expansion. Today, let’s discuss this topic.
Historical Background of the Treaty
When talking about the Treaty of Zaragoza, we must mention the 1494 Treaty of Tordesillas. At that time, Spain and Portugal drew a demarcation line to avoid conflicts in the New World. But here’s the problem: the Earth is round, so how should that line be drawn on the other side of the globe? By the early 16th century, conflicts between the two countries in Asia, especially in the Spice Islands, became increasingly intense. After Magellan’s fleet completed its circumnavigation, this issue became even more urgent.
Core Content of the Treaty
On April 22, 1529, representatives of both countries signed this historic document in Zaragoza. The core of the treaty was to establish a new demarcation line in the Pacific Ocean, located 297.5 leagues east of the Maluku Islands. Simply put, it extended the Tordesillas demarcation line to the other side of the Earth.
According to the agreement, Spain relinquished its sovereignty claims over the Maluku Islands in exchange for 350,000 ducats in gold paid by Portugal as compensation. This money was a timely relief for Spain, which was facing financial difficulties at the time. The table below shows the division of spheres of influence between the two countries:
| Country | Acquired Region | Main Resources |
|---|
| Portugal | Maluku Islands, Southeast Asia | Spices, silk |
| Spain | Philippine Islands, Eastern Pacific | Trade hub |
This division seemed clear, but was extremely difficult to implement in practice, because the navigation technology of the time could not accurately determine longitude positions.
Actual Impact of the Treaty
In the short term, the Treaty of Zaragoza did ease tensions between the two countries in Asia. Portugal consolidated its monopoly position in the spice trade, while Spain turned its attention to the development of the Philippines. In 1565, Spain formally established colonial rule in the Philippines, and Manila became an important trade hub connecting the Americas and Asia.
But from a long-term perspective, the binding force of this treaty was actually quite limited. With the rise of emerging maritime powers such as the Netherlands and England, the monopoly of overseas trade by Spain and Portugal was broken. By the 17th century, the demarcation line stipulated in the treaty had become virtually meaningless.
Lessons for Today
Looking back at [the Treaty of Zaragoza], I find it most interesting that it reflects the characteristics of international relations of that era. Two Catholic countries dividing the world through papal mediation seems absolutely incredible from today’s perspective. Of course, the indigenous people of those places being divided had no voice at all.
This treaty also reminds us that any international agreement is a product of specific historical conditions. When the balance of power changes, old rules are replaced by new ones. Spain and Portugal once dominated the world order, but eventually gave way to other powers. This is how history continuously evolves.
For those of us living in Spain, understanding this history helps us comprehend where Spain’s cultural influence in Latin America and the Philippines comes from today. Although the Treaty of Zaragoza happened 500 years ago, the historical legacy it shaped continues to influence our lives today.
