Sigurd (Old Norse: Sigurðr) is a legendary hero of Norse mythology, as well as the central character in the Völsunga saga. The earliest extant representations for his legend come in pictorial form from seven runestones in Sweden and most notably the Ramsund carving (c. 1000) and the Gök Runestone (11th century).
As Siegfried, he is one of the heroes in the German Nibelungenlied, and Richard Wagner's operas Siegfried and Götterdämmerung.
As Sivard Snarensven(d) he was the hero of several medieval Scandinavian ballads.
The name Sigurðr is not the same name as the German Siegfried. The Old Norse form would have been Sigruþr, a form which appears in the Ramsund carving that depicts the legend. Sivard is another variant name of Sigurðr; these name forms all share the first element Sig-, which means victory.
Read more about Sigurd: Völsunga Saga, Þiðrekssaga, Nibelungenlied, Archaeological Record, Parallels in Other Legends, Cultural Impact