Facts and Events
Thorgil Sprakling (also called Torkel, Torgils or Sprakalägg) was a Dane whose grandsons became kings of Denmark and England. In Knýtlinga saga he is also called "the fast". Florence of Worcester named his father as 'Ursius' (i.e. urso, Latin for bear, björn in Scandinavian languages) and Saxo Grammaticus tells the story that this Ursius/Björn was the son of a bear and a fair Swedish maiden.
Genealogical speculations of a later date (presumably first suggested by the Danish historians Jakob Langebek and Peter Frederik Suhm) would make Thorgil son of the Viking Styrbjörn the Strong, who in turn is depicted as son of Olaf Björnsson, king of Sweden. Styrbjorn's wife in the sagas, Thyra, was the daughter of Harold Bluetooth, king of Denmark and Norway. No primary source supports this theory and the theory itself is almost impossible to maintain because of the chronological inconsistencies.
His children were Ulf (died 1027), a steward and Earl of Canute the Great in Denmark, whose son became king Sweyn II of Denmark, Eilaf (also Earl of King Canute) and Gytha Thorkelsdóttir who was to marry Godwin, Earl of Wessex and become mother of Harold Godwinson, king of England.