Josef "Sepp" Dietrich (28 May 1892–21 April 1966) was a Nazi politician and member of the Schutzstaffel, serving as the first commander of Adolf Hitler's personal bodyguard; while nominally subordinate to Heinrich Himmler, his intimacy with Hitler granted him effective impunity in the unit's conduct, once even banning Himmler from the Leibstandarte barracks. During the Night of the Long Knives, Dietrich oversaw the arrest of Ernst Röhm and execution of multiple Sturmabteilung officers, and was subsequently promoted to SS-Obergruppenführer, then the highest commissioned SS rank.

An army sergeant during the First World War, despite no formal staff officer training Dietrich was given command of both Waffen-SS and regular army units during World War II, and was promoted to SS-Oberst-Gruppenführer in 1944, back-dated to 1942. His fealty to Hitler afforded him lavish publicity and numerous decorations, and following the 20 July Plot he was promoted to command of the 6th Panzer Army to enforce its loyalty. Dietrich's actual command acumen, however, was denigrated by his peers: Army High Command considered him a reckless glory hound, and Gerd von Rundstedt deemed him "decent but stupid"; allegedly, he had never been taught to read a military map.

Units under Dietrich's command were implicated in the murder of prisoners of war, notably the Wormhoudt massacre (1940) and Malmedy massacre (1944). After the war, he was convicted for war crimes by American authorities in the Malmedy massacre trial in 1946, and by German authorities for his role in the Night of the Long Knives in 1956. Following his release from prison, Dietrich joined HIAG, a denialist veterans' association for ex-SS.