Galka (Emmy E.) Scheyer (1889-1945) was an extraordinary woman: Jewish, painter, art collector, and mediator. After meeting the Bauhaus artists Alexej von Jawlensky, Lyonel Feininger, Wassily Kandinsky, and Paul Klee, she founded the artists' group "The Blue Four" along with them. To promote her "four kings" not only in Europe, she emigrated to the US in 1924. Scheyer organized exhibitions and gave lectures all over the world. The famous architect Richard Neutra designed a gallery building for her in the Hollywood Hills, where she lived and welcomed art collectors and Hollywood's high society, including Marlene Dietrich, Greta Garbo, Fritz Lang, and Josef von Sternberg. She died in Hollywood in 1945. This volume presents the papers held at the Galka Scheyer international conference in Braunschweig, the city of her birth, in November, 2019.