Palais Ephrussi is a former Ringstraßenpalais in Vienna. It was built for the Ephrussi family of financiers by Theophil Freiherr von Hansen, the architect of the Austrian Parliament Building. It is on the Ringstrasse, specifically the Universitätsring (formerly Doctor-Karl-Lueger-Ring), opposite the Votivkirche.
Unlike traditional baroque noble palaces in Vienna, the Palais Ephrussi was built in the late 19th century and is therefore considered a Ringstraßenpalais. It is five storeys high and built in the typical neo-renaissance style popular at the time of its construction.
The history of the building and the family is described in great detail in "The Hare with Amber Eyes" by Edmund de Waal, whose grandmother - Elisabeth de Waal née Ephrussi, born 1899 - spent her childhood and youth there; De Waal combined first-hand information from her with extensive research in available documents.
As noted by de Waal, shortly following Austria's annexation to Nazi Germany in the 1938 Anchluss, the building's then owner Viktor Ephrussi and his son Rudolf were arrested by the Gestapo and threatened with being sent to the Dachau Concentration Camp. Their release was conditioned upon the 78-year-old Viktor Ephrussi signing away his ownership of the building and its entire contents, including many valuable works of art and the library in which were many rare incunabula.