Sigmaringen Castle was the princely castle and seat of government for the Princes of Hohenzollern-Sigmaringen. Situated in the Swabian Alb region of Baden-Württemberg, Germany, this castle dominates the skyline of the town of Sigmaringen. The castle was rebuilt following a fire in 1893, and only the towers of the earlier medieval fortress remain. Schloss Sigmaringen was a family estate of the Swabian Hohenzollern family, a cadet branch of the Hohenzollern family, from which the German Emperors and kings of Prussia came. During the closing months of World War II, Schloss Sigmaringen was briefly the seat of the Vichy French Government after France was liberated by the Allies. The castle and museums may be visited throughout the year, but only on guided tours. It is still owned by the Hohenzollern-Sigmaringen family, although they no longer reside there.

Hohenzollern-Sigmaringen was a principality in southwestern Germany. Its rulers belonged to the senior Swabian branch of the House of Hohenzollern. The Swabian Hohenzollerns were elevated to princes in 1623. The small sovereign state with the capital city of Sigmaringen was annexed to the Kingdom of Prussia in 1850 following the abdication of its sovereign in the wake of the revolutions of 1848, then became part of the newly created Province of Hohenzollern.