Wikipedia
Thorsten (Thorstein, Torstein, Torsten) is a Scandinavian given name. The Old Norse name was Þórsteinn. It is a compound of the theonym Thor and sten "stone".
The name is one of a group of Old Norse names containing the theonym Thor, besides other such as Þórarin, Þórhall, Þórkell, Þórfinnr, Þórvald, Þórvarðr, Þórolf, most of which, however, do not survive as modern names given with any frequency.
The name is attested in medieval Iceland, e.g. Þorsteinn rauður Ólafsson (circa 850-880), Þōrsteinn Eirīkssonr (late 10th century), and in literature such as Draumr Þorsteins Síðu-Hallssonar.
The Old English equivalent of the Scandinavian name is Thurstan, attested in the 11th century as the name of a medieval archbishop of York (d. 1140), of an abbot of Pershore (1080s) and of an abbot of Glastonbury (1090s). The English surname Thurston is presumably derived from this given name. The English given name Dustin is derived from a surname which in origin may have been derived in turn from the Scandinavian given name.
As a modern given name, Thorsten and Torsten also see some popularity in the Anglosphere and in German-speaking Europe.