Question: Rhiwallon ap Cynfyn, was a Welsh King, following the 1063 invasion of Wales by Harold and Tostig Godwinson, he was an Anglo-Saxon Earl of which location, that overthrew Gruffydd, Rhiwallon and Bleddyn jointly?
Sentence (from "Battle of Stamford Bridge"): The battle has traditionally been presented as symbolising the end of the Viking Age, although major Scandinavian campaigns in Britain and Ireland occurred in the following decades, such as those of King Sweyn Estrithson of Denmark in 1069–1070 and King Magnus Barefoot of Norway in 1098 and 1102–1103.
Relevant evidence: No