[1] Flechtheim appeared in the art world shortly after 1900, with a collection of paintings by Vincent van Gogh, Paul Cézanne; French Avant garde early works of Pablo Picasso, Georges Braque and André Derain; paintings of Wassily Kandinsky, Maurice de Vlaminck, Alexej von Jawlensky, Gabriele Münter, and the Rhein Expressionists Heinrich Campendonk, August Macke, Heinrich Nauen, and Paul Adolf Seehaus [de].

Known as the Sonderbund, the exhibition brought together all avant-garde groups of artists and art movements in Europe (Expressionism, The Brücke, The Blauer Reiter, Fauvism, Cubism) for the first time.

[6] Legendary, glamorous parties in Flechtheim's gallery overflowed with the glitterati of the new Berlin: movie stars, titans of finance, prizefighters and artists of every stripe.

In March 1933, an art dealer named Alexander Vömel, a member of the SA or Brown Shirts, confiscated Flechtheim's Düsseldorf gallery.

[14] Six months after the Nazis came to power in 1933, Flechtheim, penniless, fled to Paris, and tried to find work with his former business partner, Daniel-Henry Kahnweiler and with the Mayor Gallery in London.

On August 8, 1935, Flechtheim wrote Alfred Barr of the Museum of Modern Art in New York City a letter informing him, “I lost all my money and all my pictures.” By November 1936, Flechtheim's former gallery assistant, Curt Valentin, had made a deal with the Nazis that would allow him to emigrate to New York and to sell “degenerate art” to help fund the Nazi war effort.

Upon Feldhäusser's death in 1945, the ownership of his collection passed to his mother, who brought the work to the United States and consigned it to the Weyhe Gallery in New York in 1949.

In 2018 Das Soldatenbad was restituted to the heirs of Alfred Flechtheim by The Solomon R. Guggenheim Museum and Foundation after an extensive examination of the circumstances surrounding the painting's history.

Oskar Kokoschka's "Joseph de Montesquiou-Fezensac" (1910) was sold by Alex Vömel to the National Museum of Fine Arts in Stockholm where it would later be transferred to the Moderna Museet.