In 1929 the Geymüllerschlössel was mortgaged to the Austrian National Bank. After the Nazi annexation of Austria in March 1938 the heirs of Isidor Mautner (who had died in 1930) lost all civil rights because of being Jewish and were forced to flee the country. The mortgage on the edifice was transferred to the German Reichsbank which seized the building in compensation for the outstanding debt in 1944.
The Geymüllerschlössel remained in the possession of the Geymüller family until 1842. After that it changed owners several times until it was purchased in 1888 by the textile manufacturer Isidor Mautner. In the following decades it was a much-frequented venue for social gatherings of the local theatrical and musical scene.
The Geymüllerschlössel was constructed after 1808 as a “summer villa” for the merchant and banker Johann Jakob Geymüller (1760–1834). The edifice shows a blend of Gothic, Indian and Arabic styles as was common in pleasure buildings of the period. The architect is unknown to date. Today the villa is decorated with original furniture from the first half of the 19th century and a site of the Museum of Applied Arts/Contemporary Art (MAK).
