Viken, Norway

Viken (Old Norse: Vík or Víkin) or Vika, was the historical name for a district in southeastern Norway, including the area surrounding the Oslofjord and Skagerrak, the strait running between Norway and the southwest coast of Sweden and the Jutland peninsula of Denmark.

Viken is also the name chosen for a future administrative region consisting of a merger of the counties of Akershus, Buskerud, and Østfold.

The cultural hub is centred in Oslo, but the capital of the region was formerly at Borre. This area included the important cities of Tønsberg, Oslo, Sarpsborg and Konghelle. There is disagreement among modern historians as to where the boundaries of the geographical area called Viken were during the Viking era. It is commonly believed to have comprised the historical provinces of Vestfold, Ranrike, Vingulmark, Grenland and Båhuslen.

Historically the Danish kings had established dominion over the area. Norwegian royal power began to assert itself in Viken with King Olav Haraldsson, mostly due to a sharp weakening of the Danish royal power. Olaf first declared himself king of Norway in 1015 and established control of the nation in battle, principally the Battle of Nesjar in 1016. King Olav subsequently founded the city of Sarpsborg in Viken during 1016.

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