In 1937 the Nazis held a public exhibition The Entartete Kunst of art that was considered to be modern, degenerate or subversive. As a result several artists were forced to emigrate, such as Max Ernst or were forced into exile, such as Paul Klee. Ernst Ludwig Kirchner committed suicide. Other artists awaited a much worst fate. Much art was destroyed.
Here are some examples of prints pre-1937 by considered generate artists.