In Norse mythology, Gram, (Old Norse Gramr, meaning Wrath) is the sword that Sigurd used to kill the dragon Fafnir. It is primarily used by the Volsungs in the Volsunga Saga. However, it is also seen in other legends, such as the Thidrekssaga wielded by Hildebrand. In modern times fantasy writers have paid homage to it by naming magical swords after it, thereby greatly increasing its renown.
Nowhere in the Volsunga Saga is a clear description of Gram given, but there is enough scattered throughout the story to draw a picture of the sword. Sigurd's weapons, Gram included, are described as being “all decked with gold and gleaming bright." Depending on how the text is read, the sword may or may not have a dragon emblazoned on it and/or depending on the translation been “brown of hue” Over the years this has led people to draw pictures of what they think it might have looked like.
Gram is primarily seen in the Volsunga Saga used by men in the Volsung line after Sigmund. Sigmund receives it during the wedding feast for his sister, Signy. Part of the way through the feast a strange man appears carrying a sword. Although unknown to Sigmund, this is the God Odin. He thrusts the sword into the Barnstokkr tree that grew in the middle of the hall and said, “The man to pull out this sword from the trunk shall receive it from me as a gift and he will find out for himself that he never bore in hand a better sword than this.” Soon after he departed every man made his attempt to pull the sword out of the wood. All fail except Sigmund who easily extracts it. The sword is a fine sword, and King Siggeir is covetous of it, offering Sigmund three times its weight in gold. When he refuses, King Siggeir grows angry and secretly begins plotting to steal it from Sigmund, eventually killing his father and capturing him and all of his brothers. After this the sword disappears from the narrative until Signy secretly gives it back to Sigmund as he is buried alive with Sinfjotli. After Sigmund avenges his family, he uses the sword in several battles before it is eventually broken by Odin during Sigmund's final battle with the King Lyngvi. Borghild, Sigmund's wife, takes up the two halves of the blade and keeps them for Sigurd, their son.
After Gram was broken by Odin, Borghild took the two halves and kept them for her future son. Soon the dwarven smith, Regin, comes and begins teaching Sigurd. After a period of time, he tells Sigurd of the mighty dragon, Fafnir, and the treasure which it guards, asking Sigurd to slay it for him. Sigurd agrees on one condition: that Regin make him a mighty sword capable of slaying such a monster.