Marshal
Marshal, which in most militaries of 20th century Earth was termed field marshal, was a military rank, the equivalent of which was used by the service organizations of many civilizations. As a traditional grade, marshal was the most senior general officer rank possible in an organization (a marshal outranked a general or admiral). 

The rank of marshal was usually reserved for wartime or very large military forces. During Earth's World War II, "five-star" generals (General of the Army, and later, General of the Air Force) and admirals (fleet admiral) were created to give America a rank equivalent to that of European marshals. Douglas MacArthur was one such American general who presided over the surrender ceremony of Japan in 1945. () A German equivalent of the rank was a title known as Generalfeldmarschall, which was held by Erwin Rommel, while the Reichsmarschall, held by Luftwaffe commander Hermann Göring, was something equivalent to a six-star general. (; )

On the planet Ekos, the Federation historian John Gill established a recreation of Nazi Germany, complete with an SS security organization. The commander of the SS held a type of marshal rank that held the title of Reichsführer-SS, indicated by a wreath oak leaf insignia worn on both collars. ()

The Q-entity once took on the appearance of an old Earth marshal, in a French uniform, to which Captain Jean-Luc Picard replied: "A Marshal of France... ridiculous!" Starfleet officer William T. Riker had a more analytical approach, noting that, as a marshal, Q outranked his previous disguise as a Starfleet admiral. ()

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Military ranks