According to Wikipedia: "Sigurd (Old Norse: Sigurï??r) 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 the hero in the German Nibelungenlied, and Richard Wagner's operas Siegfried and Götterdämmerung."