He fought in the Clash of Hjörungavágr in 986, and in the Clash of Swold in 1000. In 1009, he set upon England with a great warband and got a unthewly big deal of Danegeld on 1011. In 1012 he and his men went into the bondsmanship of king Ethelred the Unredy, whom they backed in 1013 against king Sweyn Forkbeard
After Sweyn's death, Thorkell had to flee to Denmark, but came back with king Canute the Great in 1015 for his greatwin of England and was made the earl of East Angleland in 1017 as Canute was became king.
In 1021, he fell out with king Canute and had to go back to Denmark. He was soon brought back to friendship with Canute who made him earl again.
While Thorkell is unqualmly a real eretidely being his line of work, moreso its early share, is bewildering and shrouded in folktale.