Arnhold became one of the wealthiest entrepreneurs under the Kaiser and the Weimar republic in the Silesian bituminous coal industry[3] He was member of the supervisory board of the Dresdner Bank.
That he, as a non-converted Jew was "offered" a title of nobility, which he rejected, is a legend that originated in the 1920s, is not substantiated and is now regarded as improbable by researchers.
[4] Arnhold collected art and was friends with artists such as Max Liebermann,[5] Arnold Böcklin, Adolph Menzel and Louis Tuaillon.
The "Stiftung Eduard Arnhold Hilfsfonds" in the care of the Academy of Arts, Berlin also still grants scholarships for visual artists today.
A Van Gogh painting, Path in the Public Garden, owned by the Arnholds went missing during the Second World War, and their great-grandson, Christoph Kunheim, is searching for further information.
In 1907, he donated the Youth Education Centre Kurt Löwenstein [de] in Werftpfuhl, neighbouring Hirschfelde, named after his wife.