Sig is the name given by Guido von List for the sigel (sigrunen) or s rune of the Armanen Futharkh, and is also used by Karl Maria Wiligut for his runes.
While the rune itself has no direct connection to National-Socialism, the sig rune used by Karl Maria Wiligut (Himmler's official occultist) in his own runic row (Wiligut runes) was used in the context of Nazi mysticism and is most commonly used to refer to the insignia of the Schutzstaffel (SS) of the Third Reich.
Guido von List in his "Armanen runes" called the rune sig, apparently based on sigel, thus changing the concept associated with it from "sun" to "victory" (German sieg), arriving at a sequence "sig", "Tyr" in his row, yielding Sigtyr (God of victory), a name of Odin. Under this name of "sig rune", the s-rune played a certain role in Fascist symbolism, most notably in the badge of the Schutzstaffel (SS), but this is credited to the Wiligut runic row of Karl Maria Wiligut as opposed to Guido von List.
The SS sig runes design was created in 1931 when Walter Heck, a sturmführer in the SS, drew two reversed and inverted sig runes side by side and noticed the similarity to the initials of the SS. Heck sold the rights of the sig runes to the SS for 2.5 Reichsmarks, and the runes were quickly adopted as the insignia of the Schutzstaffel and became one of the most commonly used forms of SS unit insignia. [1]
The Hitler Youth also used a single sig rune, but not as the emblem of its organization. The similarity to the SS insignia was an indication that the Hitler Youth was considered by many to be a central recruiting area for membership in the SS.
Wiligut wrote of the rune in Whispering of Gotos – Rune-Knowledge under the pseudonym Jarl Widar in the magazine Hagal 11 (1934), Heft 7, pp. 7-15]' in the section '6. Runes Speak!':
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