Max Oppenheimer (1 July 1885 – 19 May 1954), later known as MOPP, was an Austrian painter and graphic artist.

He studied from 1900 to 1903 at the Akademie der Bildenden Künste there under Christian Griepenkerl and Siegmund L'Allemand, and then – from 1903 to 1906 – at the Academy of Fine Arts in Prague, under Franz Thiele.

[1][2][3] Along with Egon Schiele, with whom he shared a studio in 1910 and Oskar Kokoschka he was considered as being one of Austria's leading avant-garde artists.

[5] His work was included in two art exhibitions in 1908 and 1909 in Vienna co-organised by Gustav Klimt.

[6] He was known for his portraits of contemporary cultural figures such as Thomas Mann and Arnold Schoenberg.