Bohuslän in the context of "Kingdom of Norway (872–1397)"

Viken (Old Norse: Vík or Víkin), or Vika, was the historical name during the Viking Age and the High Middle Ages for an area of Scandinavia that originally surrounded the Oslofjord and included the coast of Bohuslän. Its definition changed over time, and from the Middle Ages, Viken included only Bohuslän.

During the Viking Age, Viken was defined as the strait running between Norway and the northwest coast of Sweden and the Jutland peninsula of Denmark. It is located in what is now southeastern Norway and the northwestern Swedish province of Bohuslän. During the Viking Age, Viken was the northernmost Danish province. Control over Viken shifted between Danish and Norwegian kings in the Middle Ages, and Denmark continued to claim Viken until 1241.

The Theatre War (Swedish: Teaterkriget), Cowberry War, Cranberry War or Lingonberry War (Norwegian: Tyttebærkrigen, Danish: Tyttebærkrigen), was a brief war between Denmark–Norway and Sweden, starting on 24 September 1788, formally lasting until 9 July 1789. Although the decision to launch the attack was taken in Denmark, the majority of the attacking soldiers were Norwegians from the Norwegian army.

The attack was directed towards the region known as Bohuslän in Sweden, and was supposed to act as a diversion to relieve Russia, who was an ally of Denmark–Norway and had recently been attacked by Sweden (Gustav III's Russian War). This forced Denmark–Norway to honour their alliance between the two states that had been signed in 1773.

The Kattegat (/ˈkætəɡæt/; Danish: [ˈkʰætəkæt]; Swedish: Kattegatt [ˈkâtːɛˌɡat]) is a 30,000 km (12,000 sq mi) sea area bounded by the peninsula of Jutland in the west, the Danish straits islands of Denmark and the Baltic Sea to the south and the Swedish provinces of Bohuslän, Västergötland, Halland and Scania in Sweden in the east. The Baltic Sea drains into the Kattegat through the Danish straits. The sea area is a continuation of the Skagerrak and may be seen as a bay of the North Sea and North Atlantic Ocean, though it is not called a bay in traditional Scandinavian usage.

The Kattegat is rather shallow and can be dangerous to navigate due to many sandy, stony reefs and the tricky shifting currents. In modern times, artificial seabed channels have been dug, many reefs have been dredged either by sand pumping or boulder clearance, and a well-developed light signaling network has been installed to protect the heavy international traffic on this small sea.

Västergötland (Swedish: [ˈvɛ̂sːtɛrˌjøːtland] ), also known as West Gothland or the Latinized version Westrogothia in older literature, is one of the 25 traditional non-administrative provinces of Sweden (landskap in Swedish), situated in the southwest of Sweden.

Västergötland is home to Gothenburg, the second largest city in Sweden, which is situated along a short stretch of the Kattegat strait. The province is bordered by Bohuslän, Dalsland, Värmland, Närke, Östergötland, Småland and Halland, as well as the two largest Swedish lakes Vänern and Vättern. Victoria, Crown Princess of Sweden is Duchess of Västergötland.

Götamål is one of the six dialect areas of the Swedish language, mostly heard in Västergötland, Dalsland, northern Halland, northern Småland and Östergötland. However, it is also heard in Bohuslän and Värmland. Examples of Götamål features are vowel reduction, vowel shortening in front of endings and loss of /r/ in suffixes, such as in hästa instead of hästar, eng. horses.

The Treaty of Roskilde was negotiated at Høje Taastrup Church and was concluded on 26 February (OS) or 8 March 1658 (NS) during the Second Northern War between Frederick III of Denmark–Norway and Karl X Gustav of Sweden in the Danish city of Roskilde. After a devastating defeat, Denmark–Norway was forced to give up a third of its territory to save the rest, the ceded lands comprising Blekinge, Bornholm, Bohuslän, Scania and Trøndelag, as well as Halland.

After the treaty entered into force, Swedish forces continued to campaign in the remainder of Denmark–Norway, but had to withdraw from the Danish isles and Trøndelag in the face of a Dano–Norwegian and Dutch alliance. The Treaty of Copenhagen restored Bornholm to Denmark and Trøndelag to Norway in 1660, while the other provinces transferred in Roskilde remained Swedish.

Tryggve Olafsson (Old Norse: Tryggvi Óláfsson; Norwegian: Tryggve Olavsson; born c. 928 in Ringerike – died c. 963 in Sotnes, Bohuslän, Västra Götaland, Sweden) was the king of Viken, Norway (Vingulmark and Rånrike).