The two Archives of the sovereign (until 1850) Dukedoms of Hohenzollern-Hechingen and Hohenzollern-Sigmaringen became the core resource of the Staatsarchiv Sigmaringen. In 1849 Duke Karl Anton transferred his sovereignty to Prussia and the records concerning sovereignty and government were handed over to Prussia. Prussia founded a new Archives in Sigmaringen for this purpose. The rest of the records were kept in a house and seigniory archives in Hohenzollern. The latter was run by an archivist, who was a member of the household of the House of Hohenzollern-Sigmaringen, whereas a civil servant of the Prussian administration was head of the Prussian State Archives Sigmaringen. Only in 1938 did it get a trained archivist.
Until 1945 it was responsible for the Prussian governmental district (Regierungsbezirk) Sigmaringen. From 1945 to 1952 it was the State Archives for the new Land Württemberg-Hohenzollern responsible for its ministries, the 17 administrative districts and the agencies and courts of justice of the Land. After the foundation of Baden-Württemberg it became the State Archives for the agencies and courts in the governmental district Südwürttemberg-Hohenzollern/Tübingen. The reform of the districts and administration in 1973 changed the district Tübingen considerably and as such the area of influence for the Staatsarchiv Sigmaringen. The districts Ulm, Überlingen and Stockach were added, whereas Calw, Freudenstadt, Rottweil, Tübingen and parts of Horb and Hechingen were transferred to Freiburg. The responsibility for the regional law courts stayed with Sigmaringen.
After an extensive exchange of records with the State Archives Ludwigsburg between 1958 and 1977 Sigmaringen kept the majority of the records that had been created by the regional agencies in the South of Württemberg in the 19th and 20th centuries.
After 1945 the following deposits were added: municipal Archives Sigmaringen, the archives of the noble family Thurn und Taxis created in Obermarchtal, the Schenk von Stauffenberg Archives and in 1978 the house and seigniory archives of Hohenzollern.
In 1994 the State Archives moved into a completely renovated former palace.
Due to the reform of the administration in the Land Sigmaringen became a department of the Landesarchiv on January 1st, 2005.