The Archivo General de Indias, housed in the ancient merchants' exchange of Seville, Spain, the Casa Lonja de Mercaderes, is the repository of extremely valuable archival documents illustrating the history of the Spanish Empire in the Americas and Asia. The building itself, an unusually serene and Italianate example of Spanish Renaissance architecture, was designed by Juan de Herrera. This structure and its contents were registered in 1987 by UNESCO as a World Heritage Site together with the adjoining Seville Cathedral and the Alcázar of Seville.

The origin of the structure dates to 1572 when Philip II commissioned the building from Juan de Herrera, the architect of the Escorial to house the Consulado de mercaderes of Seville.[1]: 128 Until then, the merchants of Seville had been in the habit of retreating to the cool recesses of the cathedral to transact business.

On 12 March 1784, Juan Bautista Muñoz, a historian who was attempting to write a history of the New World, wrote to José de Gálvez, the Minister of the Indies, suggesting the idea of creating a centralized archive for documents relating to the Americas. José de Gálvez had already been considering the idea for a decade and wrote him back on 24 April, encouraging him to look in Seville and Cadiz for potential buildings that could house the archive.[1]: 128 On 24 May, Muñoz toured the former Lonja with Féliz Carazas and Lucas Cintora. He wrote to Galvez on 8 June, enthused about selecting this structure due to the fact that it was a solid structure made entirely of stone and containing sufficient space. He indicated that they would merely need to remove the recent partitions of the upper floor and restore the building to its original state.

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