I uploaded a paper about the political intentions of Snorri Sturluson to the Sagas project: THE FUNCTION OF ‘YNGLINGA SAGA’ IN HEIMSKRINGLA by Birgit Sawyer -https://media.geni.com/p14/8c/78/82/d1/53444862e3c5a04c/function_of_tghe_ynglinga_saga_original.pdf?hash=96e722713b7aad5341a269c73338ea6c2b1b0f61d13a5a52241e6fe90a114ba4.1768895999
It may or may not be useful.
The gist is this:
In Snorri’s version the Ynglings first became Norwegian kings in Vestfold, but according to
Historia Norwegiae, their original base was in Opland (in montanis), not on the coast, and in
Nóregs Konungatal (from c. 1190), based on information from Sæmund, they first ruled an unnamed realm in the east that Harald Fairhair inherited from his father, together with a WestNorwegian realm (Sogn) that he inherited from his maternal grandfather. With the help of Af Upplendinga konungum (preserved in Hauksbók from c. 1300, but probably much older), Claus Krag has traced the gradual transfer of the Ynglings' origin from the east of Norway south to Vestfold, a transfer that is fully developed in Hkr. These changes in the Yngling tradition reflect contemporary developments in Norway.
Danish hegemony
At least from the end of the 8th century the Danes had hegemony over southern Norway. In
Annales Francorum under the year 813 we read that when Charlemagne summoned rulers
for peace negotiations in Aachen, sixteen Danish magnates came, but not their kings, who
were occupied elsewhere: “The kings themselves at this time were not at home but had
marched with an army toward Westarfold [- - -], whose princes and people refused to submit
to them.” On that occasion the kings succeeded in suppressing the revolt and regained their
control of Vestfold, but we do not know for how long; from the middle of the 9th to the
middle of the 10th century Denmark underwent a period of unrest, characterized by internal
struggles for power, but with Harald Gormsson (“Bluetooth”) the Danish hegemony over
Scandinavia was again ensured, and Norway was under Danish – indirect – rule from c. 950
during the reigns of Harald, Sven Forkbeard, and Knud the Great.
The Danish hegemony (through Norwegian earls) later changed for a more direct control; after Olav Haraldsson’s death (in Stiklestad 1030), Knud placed his son Sven (Alfivason) as king of Norway, but after only a couple of years Sven was driven out of the country, when Olav’s son Magnus had been brought back from his exile. Danish kings continued, however, to maintain their claims to parts of Norway, especially Viken (the area around the Oslo fjord).
When the first Scandinavian archbishopric was established in Lund in 1104, Danish influence increased, since both the Norwegian and the Swedish churches were subordinate to the Danish archbishops. Fifty years later (1153/54), Norway escaped Lund's primacy with its own archbishopric established in Nidaros, but already in the 1160´s, the magnate Erling Skakke had to pay homage to the Danish king Valdemar I as his earl of Viken. Erling Skakke´s submission toValdemar I must have been a serious setback, but Norwegian independence of Danish control was maintained in different ways. It was in this situation that the need for a special genealogy of Norwegian kings became acute. In order to refute Danish claims to old rights in Norway, especially in Vestfold, the Norwegian genealogy began in the east: Svitjod (Sweden), proving that the Norwegian kings had their own proud lineage (during pagan times) from the important centre of Uppsala. Vestfold as the starting point for the formation of Norway was thus directed against Danish claims.
It is in this world of ideas that sagas about the Ynglings, their "genealogy" and Swedish origin, become of great immediate interest, and a poem about them is presented by Snorri to prove that Norwegian kings had long established claims to Vestfold. In the sagas, Harald Fairhair is thus made a king over Vestfold, despite the fact that his "unification" had its origin in Sogn and only comprised western Norway.
