Sigvalda ‘Sigvaldi’: According to Hkr (ÍF 26, 272), Sigvaldi jarl Strút-Haraldsson was the jarl of Jómsborg, a fortified viking settlement that lay near Wolin, Poland, and the commander of the Jómsvíkingar, a confederation of sea-warriors. Hkr (ÍF 26, 274) reports that he, at his father’s memorial feast, swears to kill or vanquish Hákon jarl. Other viking leaders take similar oaths, including Búi digri ‘the Stout’ Vésetason from Bornholm. They all go to Norway to prosecute their oath. The internal hierarchy among the vikings is never clarified, but Sigvaldi seems to be their leader, as he makes the first vow, and it is his fleet that attacks Hákon jarl’s.