Sigmund
In Norse mythology, Sigmund was a hero whose story is told in Volsunga Saga. He and his sister, Signy, are the children of Volsung. Sigmund is best known as the father of Sigurd the dragon-slayer though Sigurd's tale has almost no connections to the Volsung tales.
In the Volsunga Saga, Signy marries Siggeir. Volsung and Sigmund were attending the wedding feast (which lasted for some time before and after the marriage), when Odin, in the guise of a beggar, plunged a sword into the living tree around which Volsung's halls was built. The disguised Odin announced that the man who could remove the sword would have it as a gift. Only Sigmund was able to free the sword.
Siggeir is smitten with envy and desire for the sword. Later, Siggeir and his forces killed Volsung in battle, seized Sigmund, with his brothers, and put in stocks in the wilderness, where each night a she-wolf would come and devour one of the brothers. Before Sigmund was eaten, Signy had honey smeared over him and placed in his mouth. When the wolf came to devour Sigmund, she began licking the honey from his mouth, and Sigmund bit off the wolf's tongue, killing her.
Sigmund escaped his bonds and lived underground in the wilderness on Siggeir's lands. While he was in hiding, Signy came to him in the guise of a sorceress and conceived a child by him (Sinfjötli). Bent on revenge for their father's death, Signy sent her sons to Sigmund in the wilderness, one by one, to be tested. As each failed, Signy urged Sigmund to kill them. Finally, Sinfjötli (born of the incest between Signy and Sigmund) passed the test.
Sigmund and his son/nephew, Sinfjötli, grew wealthy as outlaws. In their wanderings, they came upon men sleeping in cursed wolf skins. Upon killing the men and wearing the wolf skins, Sigmund and Sinfjötli were cursed to a type of lycanthropy. Eventually, Sinfjötli and Sigmund avenged the death of Volsung.
After the death of Signy, Sigmund and Sinfjötli went harrying together. Sigmund married a woman named Borghild and had two sons, one of them named Helgi. Helgi and Sinfjötli ruled a kingdom jointly. Helgi married a woman named Sigrun after killing her father. Sinfjötli later killed Sigrun's brother in battle and Sigrun avenged her brother by poisoning Sinfjötli.
Later, Sigmund married a woman named Hjördís. After a short time of peace, Sigmund's lands were attacked by King Lyngi. While in battle, Sigmund matched up against an old man (Odin in disguise). Odin shattered Sigmund's sword, and Sigmund fell at the hands of others. Dying, Sigmund told Hjördís that she was pregnant and that her son would one day make a great weapon out of the fragments of his sword. That son was Sigurd.
Sigmund's story may be based on older material than that found in the Sigurd story and it is more directly involved in matters of family descent and the conquest of lands. If there is a historical person behind the Sigmund stories, it is probably a chieftain from the time of the first great Germanic migration in the second and third centuries CE.
Analogs for Sigmund's pulling the sword from the tree can be found in other mythologies (notably in the Arthurian legends). Sigmund/Siegmund is also the name of Sigurd/Siegfried's father in other versions of the Sigurd story but without any of the details about his life or family that appear in Norse Volsung tales and poems. On the other hand, the Old English poem Beowulf includes includes "Sigmund the Wælsing" and his nephew "Fiteli" in a tale of dragon slaying told within the main story. The device of the broken sword that is recast was probably drawn mainly from the Volsung account by J.R.R. Tolkien for his The Lord of the Rings (though the motif also occurs in stories about Perceval).