It was created by Decree 914/1969, dated 8 May, which provided the final configuration of the Administration archives system. The preamble text points out that its history goes back to the 16th century, since, due to the functions entrusted to it, it is the direct heir to the General Archive of Simancas and of the General Central Archive of Alcalá de Henares.
The Archive of Simancas, under the reign of Philip II, received shipments of documents from the councils and other government bodies. The lack of physical space and the distance from the court were the reasons behind the decision to create a General Central Archive in 1858, in the archbishop's palace in Alcalá de Henares.
The General Central Archive received documents from the Ministries and the bodies suppressed after the 1834 reform. After the established period, documents were sent to the Historical National Archive, until a fire in 1939 destroyed the General Central Archive.
When in 1969 the AGA was created, it consolidated the Spanish Archive System "which already existed from the previous century" and regulated the periods for transfers between the different archives. Thus, a period of 15 years was established for the Ministries to transfer their documents to the AGA, and a period of 25 for those documents that were not valid and of historical importance to be transferred to the Historical National Archive.
The first documents were deposited in the last months of 1972, although the AGA was not officially opened until 27 March 1976, due to the historical events that took place in Spain after December 1973.
As the General Central Archive had disappeared, many documents had been piled up in the central archives of the Ministries and, due to lack of space, sometimes even destroyed.
This was why the AGA received documents massively in 1972, and before they could be identified it had to collect the documents of institutions that no longer existed (the Falange, Trade Unions, Women's Department...) and documentation from the old Spanish colonies in Africa.
When the courts of Madrid were transferred to their present-day location in Plaza de Castilla, a great number of law documents were deposited in the Archive.
Despite the conditions in which these documents were received and the lack of staff, the Archive has striven to satisfy the needs of both the researchers and administrative officers. The lack of space in the Historical National Archive obstructs the transfer of documentation in accordance with the timeline indicated above, which is why the AGA is now responsible for intermediate and historical archiving functions, safeguarding documents dating back to the 18th century.
Today, the main function of the Archive continues to be to receive, by regular transfer, the documentation produced by the Spanish Central Administration that, after being kept in their own central archives, has lost administrative utility and the decrease of its enquiry frequency index shows the need for it to be transferred to an intermediate archive.
On the other hand, as stated in its creation decree, the General Administration Archive is responsible for determining which documents are to be transferred to the Historical National Archive, and which can be submitted for elimination to the High Commission of Administrative Documents Classification.
As with the rest of the National Archives, it is responsible for safeguarding, organising, describing, conserving and promoting the documents deposited in it, as they represent an important part of the Spanish documentary heritage. To do so, the Archive offers the following services: