Oskar Reichel, a Jewish doctor living in Vienna, was a major art collector. He was inspired to start collecting by the works of the Austrian painter Anton Romako, which he says he saw for the first time around 1900. There were also works by more recent artists in his collection, however. Unusually for the time, Reichel exhibited his private collection in 1913 at Galerie Miethke in Vienna, with over forty paintings by Romako as well as works by Oskar Kokoschka, Egon Schiele, Max Oppenheimer, Anton Faistauer and Albert Paris Gütersloh, but also Vincent van Gogh and Henri Toulouse-Lautrec. In subsequent years he frequently loaned his paintings and through his friendship with Arthur Roessler, director of Galerie Miethke, also met some of the above-mentioned artists. His interest prompted him to open his own gallery in the early 1920s, affiliated to the company Kunst und Wohnung, R. Lorenz, GesmbH at Josefstädter Straße 21 in the 8th district, which he also co‑managed. Following the annexation of Austria in 1938, Reichel was forced to sell some of his collection. Romako's paintings were sold through the art market and privately and ended up in some cases in Austrian museums and collections. Vita Maria Künstler and Wolfgang Gurlitt were heavily involved in these transactions.
Reichel, who ended up in the Jewish community old people's home in Vienna, died there on 7 May 1943. His wife Malvine was deported in January 1943 to Theresienstadt. After the war she lived for a short time in Vienna before moving to New York to her son Hans, who had fled to the USA in 1939. Her son Raimund had emigrated in March 1939 to Argentina via Paraguay and later returned to Vienna, where he died in 1997. The oldest son Max was murdered on 10 July 1940 at the National Socialist "euthanasia" institute at Brandenburg an der Havel.

To date, twenty-three works belonging to Reichel's collection until March 1938 have been found in the following Austrian museums and collections and restituted: Albertina, Lentos Kunstmuseum Linz, Leopold Museum-Privatstiftung, Oberösterreichisches Landesmuseum, Universalmuseum Joanneum and Wien Museum.