Sigurd is the son of lord Vylon, a descendant of Baldur, one of the Twelve Crusaders. He is the older brother of Ethlyn,brother-in-law of Quan, husband to Deirdre and father to Seliph. Altena and Leif are his niece and nephew, and Oifey is his cousin.
Prior to the events of Seisen no Keifu, Sigurd attended the Royal Academy of Belhalla, alongside his best friends Quan and Eldigan. Quan later married Sigurd's younger sister, Ethlyn.