Ulf Jarl

Ulf (or Ulf Jarl) (Ulf Thorgilsson) was a Danish earl (jarl) and regent of Denmark. Ulf was the father of King Sweyn II of Denmark and thus the progenitor of the House of Estridsen, which would rule Denmark from 1047 to 1375, which was also sometimes, specially in Swedish sources, referred to as the Ulfinger dynasty to honor him.

Ulf Jarl was the son of Thorgils Sprakalägg. His brother was Eilaf, an earl of King Cnut the Great, and his sister was Gytha Thorkelsdóttir who married Godwin, Earl of Wessex. He participated in Cnut the Great's conquest of England as one of his most trusted men. In 1015-16, he married Cnut's sister, Estrid Svendsdatter of Denmark, by whom he had sons, Svein, who later became the king of Denmark,Beorn (Bjørn), who would become an Earl in England. Chronicler Adam of Bremen also gives Ulf a son, Åsbjørn, but does not name explicitly name him as son of Estrith, as he does with Svein and Beorn. There may have also been a daughter - Harald Hardrådes saga, part of Heimskringla gives an account of Åsmund, son of Svein's sister, yet he is likely the same Åsmund named as son of Beorn in Morkinskinna. From c. 1024 he was appointed the Jarl of Denmark and King Cnut's appointee as regent of Denmark, which he ruled when the king was absent. He was also the foster-father and guardian of King Cnut's son Harthacnut.

In 1026, the Swedish king Anund Jakob and the Norwegian king Olaf II took advantage of King Cnut's absence and launched an attack on the Danish in the Baltic Sea. Ulf convinced the freemen to elect Harthacnut king, since they were discontented at Cnut's absenteeism. This was a ruse on Ulf's part since his role as Harthacnut's guardian would make him the ruler of Denmark.

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