When the French General Mortier occupied Hannover in 1803 he set up his headquarters here, and in 1804 the house accommodated Jean-Baptiste Bernadotte, Napoleon's Marshall and later King of Sweden and Norway. It was the family museum of the House of Guelph from 1866 until 1937, when it was acquired along with the Grosser Garten by the City of Hannover; in early 1939 it was comprehensively renovated. In the post-war era the house was used as a local heritage museum and residence into the 1990s.

Taken over in 1998 by the Sparkasse Finanzgruppe, the house was thoroughly renovated and restored as an historic treasure.