Towards the end of the 9th century Danish Viking armies suffered a series of major defeats in the Frankish kingdoms and in England.
After the death of the Viking rulers Sigfred and Gudfred at the battle of Leuven in 891, Denmark was, according to Adam of Bremen, ruled by a certain Helge.
Although he is not documented by contemporary sources, his son and grandson, Gnupa and Sigtrygg, are mentioned on rune stones, which speaks for his historicity.
A number of arguments have been put forward to support this, including the existence of a rune stone in Saedinge on Lolland that mentions Swedes.
[5] The placement of the rune stones associated with the dynasty has led to the conclusion that the kings ruled from Hedeby in South Jutland, one of the most important commercial centers in Viking Age Scandinavia.