The Siklings were a villainous clan

Norse clans

The Scandinavian clan or ætt was a social group based on common descent or on the formal acceptance into the group at a þing.-History:...

 in Norse mythology

Norse mythology

Norse mythology, a subset of Germanic mythology, is the overall term for the myths, legends and beliefs about supernatural beings of Norse pagans. It flourished prior to the Christianization of Scandinavia, during the Early Middle Ages, and passed into Nordic folklore, with some aspects surviving...

. In Skáldskaparmál

Skáldskaparmál

The second part of Snorri Sturluson's Prose Edda the Skáldskaparmál or "language of poetry" is effectively a dialogue between the Norse god of the sea, Ægir and Bragi, the god of poetry, in which both Norse mythology and discourse on the nature of poetry are intertwined...

, Snorri reports that they are descended from a Sigar who was the son of Halfdan the Old

Halfdan the Old

Halfdan the Old was an ancient, legendary king from whom descended many of the most notable lineages of legend...

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Hversu Noregr byggðist gives more detail to the Sikling clan informing that Sigar had the two sons Siggeir

Siggeir

Siggeir is the king of Gautland , in the Völsunga saga. In Skáldskaparmál he is given as a Sikling and a relative of Sigar who killed the hero Hagbard...

 and Sigmund, who had the son Sigar

Sigar

The name Sigar can refer to three people in Scandinavian mythology, surrounding the legends of Sigurd the dragon slayer. One of them only appears as the friend of Helgi Hjörvarðsson in the eddic lay Helgakviða Hjörvarðssonar...

 (the one who hanged Hagbard).

Siggeir

Siggeir

Siggeir is the king of Gautland , in the Völsunga saga. In Skáldskaparmál he is given as a Sikling and a relative of Sigar who killed the hero Hagbard...

 is the Geatish king who murdered Völsung

Volsung

In Norse mythology, Völsung was the son of Rerir and the eponymous ancestor of the ill-fortuned Völsung clan , including the greatest of Norse heroes, Sigurð...

 and most of his family. The younger Sigar is the one who kidnapped one of Haki

Haki

Hake, Haki or Haco, the brother of Hagbard, was a famous Scandinavian sea-king, in Norse mythology. He is mentioned in the 12th century Gesta Danorum, and in 13th-century sources including Ynglinga saga, Nafnaþulur, Völsunga saga...

's daughters and murdered a second one according to the Völsunga saga

Volsunga saga

The Völsungasaga is a legendary saga, a late 13th century Icelandic prose rendition of the origin and decline of the Völsung clan . It is largely based on epic poetry...

and hanged Hagbard

Hagbard

Hagbard , the brother of Haki and son of Hamund, was a famous Scandinavian sea-king in Norse mythology. He is mentioned in Skáldskaparmál, Ynglinga saga, Nafnaþulur, Völsunga saga and Gesta Danorum...

 according to Skáldskaparmál and Gesta Danorum

Gesta Danorum

Gesta Danorum is a patriotic work of Danish history, by the 12th century author Saxo Grammaticus . It is the most ambitious literary undertaking of medieval Denmark and is an essential source for the nation's early history...

(book 7). The last murder is also referred to in Háleygjatal

Háleygjatal

Háleygjatal is a skaldic poem by Eyvindr skáldaspillir made in honour of Haakon Sigurdsson and his ancestors, in the end of the 10th century.The poem is only partially preserved in disjoint parts quoted in Skáldskaparmál, Heimskringla and two other manuscripts of kings' sagas. It appears to be a...

and in Ynglingatal

Ynglingatal

Ynglingatal is a skaldic poem listing the kings of the House of Ynglings, dated by most scholars to the late 9th century.The original version is attributed to Þjóðólfr af Hvini who was the skald of a Norwegian petty king named Ragnvald the Mountain-High and who was a cousin of Harald Fairhair...

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