This is the German parody forgery of the 1935 Great Britain 1/2 penny Silver Jubilee stamp.
Changes to the design include Stalin in place of King George V, and “This war is a / Jewsh war” in place of “Silver Jubilee / Half Penny.” The dates have also been changed from the original 1910-1935 to 1939-1944.
The Star of David and hammer and sickle also appear throughout the design.
For more on this issue, see Propaganda and Espionage Philately, by SGM Herbert A. Friedman (Ret.).