The Treaty of Alcáçovas, signed in 1479, ended the War of Castilian Succession and divided the Atlantic world between Portugal and Castile: Portugal received dominion over the African coast, the Azores, Madeira, and the Canary Islands (partially), while Castile's claim to the throne was recognised. It was the first treaty to partition non-European territories between European powers and set a legal template for the Age of Exploration. The treaty also ended decades of dynastic rivalry between the Iberian crowns.

The Treaty of Alcáçovas helped inaugurate the Iberian age of oceanic expansion that would give rise to some of the greatest epic poetry in European literature, most notably Luís de Camões' Os Lusíadas (1572), which celebrated Portuguese maritime achievement as the fulfilment of national destiny. The division of the Atlantic also eventually produced the 1494 Treaty of Tordesillas, the geopolitical framework within which Columbus sailed — and within which the encounter with the Americas would transform European self-understanding and poetic imagination. The court of Portugal became one of the most sophisticated literary centres in Europe during this period of expansion.