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A national socialist ideology popularized by Adolf Hitler and were later adopted during his rule over Germany between 1933 to 1945. Notable for its extreme Pan-German/Nordic racial nationalism and disregard of other races as inferior, especially the Poles, Serbs and Jews (later Russians and Romani), as well as a systematic extermination of their victims.
For use on posts with the NSDAP emblem or SS Insignia (sig runes) runes/uniforms, or otherwise clear Nazi markings such as the Totenkopf (corpse's skull), along with depictions of Nazi Germany in general.
Note that "SS-inspired", but imaginary uniforms do not qualify for the tag, nor does general German World War II imagery, such as the eagle and swastika, Iron Cross, or German Military units and equipment, unless they fit the earlier mentioned criteria.