The Blutfahne, or Blood Flag, is or was a Nazi Party swastika flag that was carried during the attempted coup d'état Beer Hall Putsch in Munich, Germany on 9 November 1923, during which it became soaked in the blood of one of the SA men who died. It subsequently became one of the most revered objects of the Nazi Party. It was used in ceremonies in which new flags for party organisations were consecrated by the Blood Flag when touched by it.

The Beer Hall Putsch, also known as the Munich Putsch, was a failed coup d'état by Nazi Party leader Adolf Hitler, Generalquartiermeister Erich Ludendorff and other Kampfbund leaders in Munich, Bavaria, on 8–9 November 1923, during the Weimar Republic. Approximately two thousand Nazis marched on the Feldherrnhalle, in the city centre, but were confronted by a police cordon, which resulted in the deaths of 15 Nazis, four police officers, and one bystander.