Siefredus of Northumbria

[1] The historian Alfred Smyth and others have proposed that Siefredus may be the same person as the Sigfrith that led a Viking fleet against Wessex in 893.

[1] Though there is no way to know for sure if this Sichfrith and the one mentioned in the Irish Annals are the same, it is certainly plausible, and it is likely that there was contact between the Viking kingdoms of Northumbria and Dublin during this period.

Smyth has proposed Siefredus was a Northumbrian who sailed to Dublin after his fleet landed troops in Wessex.

According to this theory Siefredus failed to take the city and caused the strife among the Vikings of Dublin noted by the Annals of Ulster.

[4] An altogether different suggestion, put forward by Cannon and Hargreaves, is that Siefredus is identical to his successor, Cnut.