[3] In the 1920s he opened a gallery in Cologne, where Salz sold works by Marc Chagall,[5] Hans Arp, Georges Braque, and James Ensor.
He purchased works of art directly from artists such as André Derain,[6] Maurice de Vlaminck, Édouard Vuillard, Pierre Bonnard, and Chaïm Soutine.
[8] This period also saw several portraits of Sam Salz, including a watercolor by James Ensor,[9] a pastel by Édouard Vuillard,[10] and a photograph by August Sander.
[14][15] His clients have included renowned museums and collectors like Albert C. Barnes,[16] Paul Mellon, Robert Lehman,[4] Henry Ford II, David Rockefeller, and William S.
[17] Among Salz's friends were writer Erich Maria Remarque,[18] pianist Vladimir Horowitz,[19] and painter Diego Rivera.
[3] In Jerusalem, Salz underwrote the construction of a small park (גן משה זלץ) named for his father, who had been murdered by the Germans during the Holocaust.
[24] During the Kennedy administration, he donated to the White House the painting The Declaration of Independence of the United States of America, July 4, 1776 by Charles Édouard Armand-Dumaresq.