 His many friends included such diverse people as Hanna Reitsch, Lida Baarova, Hans Fallada, Anny Ondra, and Fritz-Dietlof von der Schulenburg.After World War II, Wieman moved to Switzerland with his wife, stage actress , there in 1969 he died of cancer.Mathias and his wife Erika (died in 1972) were cremated and the ashes buried in the in the in Osnabrück.