The valknut (Old Norse valr, "slain warriors" + knut, "knot") is a symbol consisting of three interlocked triangles, and appears on various Germanic objects. A number of theories have been proposed for its significance.
The name valknut is an unattested modern invention used to describe the symbol, and was not used contemporarily when the symbol was used. The valknut has been compared to the three-horned symbol found on the 9th century Snoldelev Stone, and may be related to it.
Traditional forms 
The historically attested instances of the symbol appear in two traditional, topologically distinct, forms. The symbol appears in unicursal form, topologically a trefoil knot also seen in the triquetra. This unicursal form is found, for example, on the 7th century Tängelgårda stone on the island of Gotland, Sweden. The symbol also appears in tricursal form, consisting of three linked triangles topologically equivalent to the Borromean rings. This tricursal form can be seen on one of the Lärbro stones, also on Gotland, Sweden, as well as upon a ring found in the River Nene in England, and on a bedpost found within the 834 Oseberg ship burial from Slagen, Norway. Although other forms are topologically possible, these are the only attested forms found so far.
Hrungnir's heart 
Chapter 17 of the 13th century Prose Edda book Skáldskaparmál contains the following description of the heart of the Jötunn Hrungnir; "Hrungnir had a heart that was famous. It was made of hard stone with three sharp-pointed corners just like the carved symbol hrungnishjarta [Hrungnir's heart]." Comparisons have been made between this symbol description and the symbol known as the valknut.
Odin and mental binds 
For instance, beside the figure of Odin on his horse shown on several memorial stones there is a kind of knot depicted, called the valknut, related to the triskele. This is thought to symbolize the power of the god to bind and unbind, mentioned in the poems and elsewhere. Odin had the power to lay bonds upon the mind, so that men became helpless in battle, and he could also loosen the tensions of fear and strain by his gifts of battle-madness, intoxication, and inspiration.
Davidson says that similar symbols are found beside figures of wolves and ravens on "certain cremation urns" from Anglo-Saxon cemeteries in East Anglia. Davidson says that Odin's connection to cremation is known, and that it does not seem unreasonable to connect with Woden, the god of the dead in Anglo-Saxon England. Additionally, Davidson proposes further connections between Odin's role as bringer of ecstasy with the etymology of the names Wodan (related to wut "high mental excitement, fury, intoxication, or possession") and the later Oðinn (from the adjective óðr meaning "raging, furious, intoxicated").
Due to the Norwegian name for the symbol, valknuter, and the fact that the symbol appears on picture stones with Odin and on burial gifts in the Oseberg ship burial, Rudolf Simek states that the symbol may have been associated with religious practices surrounding death.
As Borromean rings on the Stora Hammars I stone
Modern use 
The valknut symbol plays a role in modern Germanic Neopagan faiths, where numerous explanations and interpretations of the symbol are given, has been used by various political groups, and sometimes sees use in modern popular culture. Examples of usage include the Swedish pulp and paper manufacturer and consumer goods company Svenska Cellulosa Aktiebolaget's employment of a triquetra valknut as their logo, which can be commonly seen on many products produced by the company. The Deutscher Fußball-Bund (DFB) uses a logo for the German national football team (since 1991) that is inspired by the unicursal form of the valknut. According to the Anti-Defamation League, the symbol has been appropriated by some white supremacists for use as a racist symbol.
See also 
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