
On this day in 1493, a papal bull by the name of inter caetera (“Among other works”) was issued by Pope Alexander VI from the Vatican. The decree stated that the Americas would be split into two spheres of influence between European powers: Spain would get to explore the Western half of the continent, and Portugal, the Eastern half. Tensions had risen between the countries as explorer Christopher Columbus bumbled back to Lisbon in 1493, fresh off the “success” of his first voyage to the Azores beginning the year prior. Before his voyage, Columbus had offered his services to the Portuguese government; when they turned him away, citing problems with his incredibly flawed navigation plan, the persistent explorer turned instead to the Spanish. Frustrated at Columbus’ improbably success – which opened up tremendous possibilities for exploration and economic growth – the Portuguese claimed the Spanish had violated territorial agreements.

The dispute grew, and the Pope was called in to mediate; the resulting bull stated that the Spanish and Portuguese would be allowed to explore the incredibly valuable – and now, well within reach – Americas, on either side of a line “… one hundred leagues towards the west and south from any of the islands commonly known as the Azores and Cape Verde.” Neither party was satisfied with inter caetera, however, and the Pope’s bull was promptly ignored. A new agreement, the Treaty of Tordesillas, followed; the demarcation line was moved farther west, and Spain was given enhanced access to the Pacific. In the following centuries, Portugal and Spain developed massive colonial empires in Southeast Asia and the Americas. Using their new territories – and the resources and manpower that entailed – the two powers grew to dominate European politics.

Just as the Portuguese and Spanish had ignored the Pope’s agreement, the rest of Europe ignored the Treaty of Tordesillas. Fairly quickly, Portuguese holdings in the Pacific were overrun by the Dutch and Spanish territories in North America were contested by the British, French and later the Americans. The twin powers – rivals till the end – began to languish, and their lessened colonial influence corresponded with a loss of power in the European system. Although inter caetera and ensuing treaties failed to grant Portugal and Spain the long-lasting world dominance they craved, the nations certainly left their mark on the “New World”.