With his wife
Thekla (1884–1968), née Pauson, he had an art collection of around 4,000 works that contained important
German Expressionist works. Hess was a philanthropist, donating numerous artworks to museums in Germany. Gifts included the Johannes Driesch (1901 - 1930) drawing,
Familie und Liebespaar, and Lionel Feiniger's
Viadukt to the Museum für Kunst und Heimatgeschichte in Erfurt. He also loaned artworks to museums, such as
Landungssteg by Lionel Feiniger and
Tänzerinnen by Erich Henkel. These and other gifts and loans he made to museums were later seized by the Nazis, as were works from his private collection. Others were sold to finance the escape and survival of his family. == Hess' death and the family's fate under the Nazis ==