The Archive General of Indias of Sevilla was created in 1785 at the request of King Carlos III, with the aim of centralizing in one place the documentation referring to the administration of the Spanish colonies until then dispersed in various archives: Simancas, Cádiz and Sevilla.
The archive conserves about 43,000 files, with some 80 million pages and 8,000 maps and drawings that come, mainly, from the metropolitan organisms in charge of the administration of the colonies. It was declared a World Heritage Site by UNESCO in 1987, next to the Cathedral and the Reales Alcázares.
After the discovery of America, and the choice of Seville as the exclusive port of trade with this continent, the commercial activity of the city increased. The place used by merchants to carry out their mercantile activities were the steps of the Cathedral. Its central point was the so-called Fuente del Hierro, located in the place currently occupied by the Church of the Tabernacle. During the second half of the 16th century, the Cabildo de la Catedral, to avoid the excesses committed by the merchants, who did not hesitate to complete their agreements inside the temple on rainy days, installed columns with chains around the temple and hired sheriffs to avoid the passage of pack animals on the street. In response to complaints from the Metropolitan Council, King Felipe II decided to build a building to house the Lonja, which would be carried out on the same Avenue, next to the Cathedral, and would end up being the headquarters of the Archivo de Indias. Its construction began in 1584, not opening to use until 1598.
The House Market of Merchants of Seville, built during the reign of Felipe II between 1584 and 1598, by Juan de Mijares, on plans by Juan de Herrera, was chosen as the seat of the archive, a task that it carries out to this day.
It is an exempt building, with square plant and central patio, seated on a podium, it has two floors of height, it combines red bricks and stone elements on its exterior, a combination that would continue in different Sevillian buildings. Inside is the central courtyard, built of stone and wide proportions, showing arches fastened on the pillars with half columns. Stresses the current main staircase of the building, Lucas Cintora project, which was made after the construction of the building, at the end of the eighteenth century, and is decorated with marble veneers. A lantern dome opens on the staircase.
Between 1999 and 2005 the works of conservation and recovery of the property carried out by the architect Antonio Campos Alcaide take place. They propose a redefinition of the functional program of the building, as well as an update of the facilities. With the intention of safeguarding the building without any spatial alteration and taking advantage of the existence of a small basement, its extension is proposed by means of a perimeter gallery.
Within the intervention, the action on the building of the old Cilla del Cabildo Catedralicio, located on Santo Tomás Street, is noteworthy, for its incorporation as the second auxiliary headquarters of Casa Lonja.
Two fundamental reasons frame the foundation of the Archive General of Indias. On the one hand, the lack of space in the General Archive of Simancas, the central archive of the Spanish Crown. On the other hand, in line with the spirit of the Enlightenment, the desire to write a history of the Spanish conquest and colonization that would respond to the foreign writings that had dealt with the subject.
The person in charge of the project was José de Gálvez y Gallardo, Secretary of the Indies, being entrusted with the academic and historian Juan Bautista Muñoz, Cosimographer of the Indies, of his execution.
In October 1785 the first documents began to arrive at the Archive. Since then, and in different remittances, the funds of the main institutions related to the Indies have been incorporated to convert the archive into the main documentary repository for the study of the Spanish administration in the New World and the Philippines. At the time of making the file, the year 1760 is taken as the dividing date between the administrative and the historical, so that the documents prior to that date had to be sent to the Archive of Indias, leaving the documentation after that date to the service of the agencies that had produced the documents.
The documents that today preserve the file occupy more than nine linear kilometers of bookshelf. It is about 43,000 files with some 80 million pages and 8,000 maps and drawings that come, mainly, from the metropolitan agencies responsible for the administration of the colonies.
The Council of the Indies, in the XVI-XIX centuries.
The House of the Contracting, in the XVI-XVIII centuries.
The Consulates of Seville and Cádiz, in the XVI-XIX centuries.
The Secretariats of State and of the Universal Office of the Indies, of State, Grace and Justice, Treasury and War, in the XVIII-XIX centuries
The Secretariat of the Court of Arrivals of Cádiz, in the XVIII-XIX centuries
The Commissariat Intervenor of the Public Treasury of Cádiz, the General Directorate of the Post Office Income, in the XVIII-XIX centuries
The Overseas Court of the Court of Accounts, 19th century
The Real Company of Havana, in the XVIII-XIX centuries.
Only some documents come directly from colonial organisms (Captaincy General of Cuba, XVIII-XIX centuries, repatriated from Havana after the defeat in the Spanish-American War) or from individuals related to the colonial administration (such as those of the XV Duke of Veragua, direct descendant of Christopher Columbus, XV-XVIII centuries, acquired in 1930, General Polavieja, one of the last general captains of the Philippines, 1876-1898, or those of the Viceroy of Peru, Abascal, 1804-1859).
It is currently the largest archive on the activity of Spain in America and the Philippines containing information on political history and social history, economic history and mentalities, the history of the Church and the history of art or geography of those territories. It holds a large number of pieces of incalculable historical value: autograph texts by Christopher Columbus, Fernando de Magallanes, Vasco Núñez de Balboa, Hernán Cortés or Francisco Pizarro. Their documents are analysed and consulted by the researchers who spend each year through the archive.
The Archive is one of the general archives (together with that of the Crown of Aragon and that of Simancas) belonging to the Spanish State. In 1987 it was declared a World Heritage Site by Unesco next to the Cathedral, the Giralda and the Reales Alcázares de Sevilla.
The Archive is governed by the Board of the General Archive of the Indies, created by Royal Decree of June 34 (BOE June 25, 2005) in which the Ministry of Culture, the Junta de Andalucía, the City Council of Seville, the Council participate Superior of Scientific Investigations and the Universities of Seville, being also vocal born, different personalities of the world of the culture.

Fuente: (web) Wikipedia.