The Fairhair dynasty may, however, be an artificial construct. The murder of king Harald Greycloak in 970 brought an end to the rule of the immediate family of his grandfather, Harald Fairhair, and Norway was ruled instead by the Danish king and his proxies for 25 years. Olav I of Norway, who had been raised overseas in obscure circumstances, forcibly conquered the kingdom. His death resulted in another 15-year period of Danish rule before the successful Viking raider, Olav Haraldson in turn conquered the kingdom and was succeeded by his son and then by his half-brother, Harald Hardråde, himself a famous Viking. The later heroic sagas would give each of these three warrior kings distant descents from Harald Fairhair. However, it has been proposed (most vociferously by Claus Krag) that the genealogical lines connecting Harald Fairhair via otherwise obscure individuals to Olav I, Olav II and Harald Hardråde are a political fiction, founded on a later attempt to legitimize their rule and that of Hardråde's descendants, as well as to provide a claim to the region of Viken (the area around the present-day Oslo), a claim challenged by the Danes. Adherents of this proposal consider Harald Hardråde to be the first king of the lineage that would later rule the realm, and that his claim at the time rested solely on being maternal half-brother of Olav II, and not a distant descent from Fairhair. Descent from the same mother was not in Germanic understanding a proper dynastic tie, and thus Harald Hardråde's legitimacy necessitated the fabrication of unbroken male line descents for him and his two predecessors from Fairhair. These fabricated descents are what would appear in the pseudo-historical sagas of "Heimskringla".