Yet the real-life Kattegat is nothing like its representation on the small screen. Just where exactly is Kattegat, and was it ever the locus of power in the Viking Age?

Kattegat on the small screen

Since 2013, many around the world have been fixated on the adventures of Ragnar Lothbrok in the historical drama television series Vikings. Based on the sagas of Ragnar Lodbork, the series follows his rise to power as well as his adventures around the Viking Era milieu, from the British Isles to the Kievan Rus, from Sicily to North America.

With a cast of over 496 spread across six series, the show has been praised for a renewed interest in the Viking Age as well as its attempt at broad historical accuracy. Beginning with the raid on Lindisfarne in 793 CE, the series sets about to tell the story of the Viking period up until the defeat of the Vikings at the Battle of Edington in 878 CE.

The show is set in the region of Kattegat. This is a strategically important area of southern Norway, nestled between fjords, with access to the sea. Furthermore, the area is said to be rich in soil, allowing significant farming of the land. What starts out as a small collection of villages soon expands as Ragnar ascends to power. By the middle of the series, Kattegat has been transformed by the inclusion of vast valleys surrounding it and is now a walled medieval city made rich from the pickings during the various Viking sieges of Paris.

In the series, characters travel, on horseback, from Hedeby, in southern Denmark, meaning that Kattegat must be connected to southern Scandinavia by land. Kattegat is also the scene of two major sieges during the series… but you'll have to watch the series to find out who falls in battle…

Kattegat in real life

Moving away from the small screen and back to reality, what do we know about Kattegat? First and foremost, though it is a location, it is slightly wetter than the one portrayed in Vikings.

Kattegat (Dutch for "Cat Hole" – more on this later) is a 30,000-kilometer squared sea that lies between southern Sweden and Denmark. It is bordered by the Skaggerak Sea in the north and the Danish islands and Baltic Sea in the south. On its western flank lies the Jutlandic peninsula (housing the majority of the area of Denmark), whilst on its eastern flank lies the Swedish provinces of Halland, Bohulsän, Halland, Skåne, and Västergötland. Several large port cities lie on Kattegat's shores, including Gothenburg, Aarhus, and Aalborg.

The Hanseatic League established one of its four offices at Bryggen in Bergen, Norway. Photo: Prometheus Design / Unsplash

The sea has gotten its name from the time of the Hanseatic League. This Northern European trading network saw significant shipping throughout member cities. The Danish straits were said to have such narrow passable waters – at one point less than 4 kilometers wide – coupled with many reefs that Dutch traders compared it to a passage (gat – passage) so narrow that only a cat (katte – cat) could squeeze through.

The sea took on an increasingly important role from the early 15th century CE for the Kingdom of Denmark. The Kattegat was, up until the mid-18th century, the only way both into and out of the Baltic Sea region. This was a bustling area of global commerce thanks to the Hanseatic League. The Danish King extracted a toll charged with the passage of goods through the Kattegat. This accounted for almost two-thirds of the Kingdom's income during the 16th and 17th centuries CE.

Is there any historical basis for Kattegat?

Putting aside the fact that the Kattegat is a sea and not a location nestled amongst fjords somewhere in southern Norway, is there any historical truth in the Vikings depiction of Kattegat?

Throughout Vikings, we see Kattegat grow from a collection of small huts into a much larger bustling metropolis completed with farms, walls, and significant fortifications. This transformation during the early medieval period mirrors that of Tonsberg, which is located on the south coast of Norway. Historically named Tunsberg, it was founded by Harald Fairhair in the 9th century CE and was an ancient capital of Norway.

Tønsberg has a long and proud Viking tradition as it was said to have been founded shortly after the epic Battle of Hafrsfjord took place in 871 CE. The victorious Viking chief, Harald, would unify the several petty kingdoms under a single monarch for the first time in Norwegian history. Historians now regard Harald I Fairhair as the first legitimate King of Norway and his unification as an important step on the path to the later medieval Kingdom of Norway. A proto-parliament, Haugating, the site for the proclamation of Kings, was situated near the town, and the famous Oseberg Viking Ship was discovered there in the early 20th century.

Kattegat should be seen, at least in Vikings, as a sort of a metaphor for the close proximity of Scandinavian Vikings throughout the early medieval period. It was only after the 11th century that the realms of Denmark, Norway, and Sweden would become firmly established and secure.

We get to provide readers with original coverage thanks to our loyal supporters. Do you enjoy our work? You can become a PATRON here or via our Patreon page. You'll get access to exclusive content and early access.

Do you have a tip that you would like to share with The Viking Herald?
Feel free to reach out to discuss potential stories that may be in the public interest. You can reach us via email at with the understanding that the information you provide might be used in our reporting and stories.