restricted to the eastern coasts) regional magnates—thegns, holds and high-reeves—exercised a considerable degree of independence from the ealdormen. One such example was the magnate Thurbrand, a hold in Yorkshire, probably based in Holderness, whose family were frequently at odds with the ruling earls at Bamburgh. Ancestry Historians generally claim Siward to be of Scandinavian origin, a conclusion supported by the Vita Ædwardi Regis, which states that Siward was "[called] Digri in the Danish tongue" (Danica lingua Digara). Legendary material incorporated in the Vita et passio Waldevi comitis (or simply Vita Waldevi), the hagiographic biography of Siward's son Waltheof, states that Siward was the son of a Scandinavian earl named Bjorn and provides a genealogy claiming that he was the descendant of a polar bear, a commonplace piece of Germanic folklore. Historian Timothy Bolton has recently argued that the similarities between these genealogies is evidence of a shared family tradition between the descendants of Siward and Thorgil Sprakling. Bolton hypothesized that Siward's alleged father Bjorn was probably a historical figure, a brother of Thorgil Sprakling. Siward would then have been first cousin to Earl Ulf, the earl of Denmark who married Cnut's sister Estrith and founded the dynasty of Danish monarchs that eventually succeeded Cnut's. Bolton argued that the Sprakling family had only recently risen to prominence in Scandinavia, and so Siward's career in England was another indication of that family's success in Scandinavian politics. The Vita Waldevi provides further legendary detail of Siward's journey from Scandinavia to England. According to the Vita, Siward passed through Orkney, killing a dragon there before moving on to Northumbria. There he encountered another dragon, before meeting an Oðinn-like old man on a hill, who handed him a raven banner and instructed him to proceed to London to receive the patronage of the king of England. Career under Cnut, Harold and Harthacnut The exact date and context of Siward's arrival in England are unknown, though the Vita Waldevi offers a legendary account. Charters dating to 1019, 1024, 1032, 1033 and 1035 mention a Si[ge]ward Minister, "the thegn Siward", but it is impossible to securely identify any of these names with the man who became Earl of Northumbria. The earliest certain contemporary record of Siward occurs in a charter of King Cnut to Ælfric Puttoc, Archbishop of York, in 1033. This charter attestation can be identified as Siward the earl because he is styled dux ("earl").