Our history

The fortress of Bohus is owned and administered by Statens Fastighetsverk, the Swedish National Property Board and it is rented by the municipality of Kungälv since many years back.

Together they are responsible for a more than 700 years of cultural heritage which attracts 40 000 visitors every year, fascinated by Bohus history and its memorable surroundings.

Bahus and later Bohus

Originally the fortress was called Bagahus, a name that through time transformed into Bahus and later Bohus. The province Bohuslän is named after it. Almost no other place can claim so much Nordic history as Bohus fortress and the islet of Fästningsholmen, on which it is located. Since its foundation in 1308, Bohus has been besieged 14 times by Swedes, Norwegians and Danes – a Nordic record – but the fortress has never been conquered. Bohus remained impregnable and the motivation is to be searched in an old legend about a dog dragging the first stone of the building.

Today, Bohus is surrounded by beauty and peace, but the echo of explosions and the memory of gunpowder smoke still remain within its stone walls. If stones could speak they would whisper stories about kings, saints, struggles for power, traitors and prisoners.

The territory around Göta River’s estuary is an old Nordic borderland, the Swedes possessed just a thin portion of land, which they acquired in the 13th century. South there was Denmark (Halland) and Norway reached so far as to Hisingen Island. Only the two towns of Lundby and Tuve, located south of the Norwegian border, belonged to Sweden.

The city of Gothenburg was yet not founded, the most important shipping port of Western Sweden was Lödöse, a town now located in Lilla Edets municipality. Along the Norther River laid the ancient Norwegian town of Kungahälla, which was Norway’s springboard towards the continent and its southernmost outpost. Central control was weak and the Kings’ power relied on kinship and alliances, which often stretched beyond boundaries. Country limits were not easy to determine.

In 1101, a meeting between the Swedish, Danish and Norwegian kings took place in Kungälv to “delineate borders and promote peace”. That was the first recorded attempt to set country borders in the North.

In the beginning

In the early 14th century, a struggle for power broke out between King Birger of Sweden and his two younger brothers, Duke Erik and Duke Valdemar. Duke Erik was married to the Norwegian Princess Ingeborg, daughter of King Håkon V Magnusson, therefore he had strong connections with the Norwegian Royal House.

Thanks to his marriage, Duke Erik obtained the stronghold on Ragnhildsholmen, built in the 13th century. At the time, the stronghold was located on an island, in front of the Norwegian town of Kungahälla, but today there is only ruins to be found at Hisingen’s shore. Ragnhildsholmen was an important foothold for Duke Erik and Duke Valdemar, who rapidly gained control over major parts of nowadays western Sweden. Håtunaleken and Nyköpings gästabud are two well known historical events that occurred during this fight for power, which closely resembled a Nordic Civil war.

None of the Northern Kings had any interest in letting the Dukes Erik and Valdemar gain more strength, which sealed the brothers’ fate. The old alliances had weakened and the Norwegian King Håkon V Magnusson demanded his son-in-law Duke Erik to give back the territory of Ragnhildsholmen. The Duke refused and the stronghold on Ragnhildsholmen was besieged by the Norwegian king in an attempt to reclaim it, but with no success.

According to Erikskrönikan, one of the oldest written sources about Swedish history, it was the Danish Count Jacob Nielsen who exhorted the Norwegian King to build a new fortification on the high cliff where Göta River divides. This way the Norwegian king and his allies were able to take control of all communication from and to Ragnhildsholmen, Soon enough the old fortress lost its leading role, due to the better strategic position of Bohus, which controlled the river and took over the function as Norway’s southernmost outpost.

When Bohus was founded, it was a simple building mostly made of wood, but it rapidly transformed into a stone castle. Some stones from the old stronghold Ragnhildsholmen were used to build its walls. Bohus became one of the most potent strongholds in the North, constantly developing its bastions and wall construction. During the Reformation in the 16th century, many catholic monasteries were demolished and their stones were transported to Bohus. After being a Union for a long time, the Nordic countries split apart. Sweden left the so called Kalmar Union in 1523 under the leading of King Gustav Vasa, but Denmark-Norway were to remain the strongest power in the region for yet a hundred years.

It was a time of war and battles, and during the Northern Seven Years’ War, Bohus was besieged no less than six times by the Swedes, but without success. In1566 the Swedes managed to enter one of the four towers, The Red tower, and raised the Swedish flag on its top.

But the defenders lit the gunpowder in the ground storage of the tower, which led to a vast explosion. The whole tower was destroyed and the Swedes in it “were thrown up in the sky like crows and other birds and no one got out alive”, according to a Danish eyewitness.

Bohus needed to be restored after several sieges. The Danish King Christian IV (1677-1648) transformed Bohus into a magnificent Renaissance castle, with fortified bastions, as a defense against newly developed artillery.

The Roskilde Treaty in 1658

The town Kungahälla was moved upstream to the island of Fästningsholmen in 1613, partly due to the fact that the Swedes had burned down all the houses during the latest war. The relocation would prove to be unlucky, because the town moved to an even more exposed location as when Bohus fortress was under siege again in 1645. Soon, the Norwegian-Danish period would come to an end.

With the Roskilde Treat in 1658, Bohuslän and several other provinces, became Swedish territory. Since its foundation the fortress has been besieged 14 times, but has never been conquered in battle. After the Swedes became lords of the fortress, the Danes and Norwegians tried to reclaim it on two occasions, both times with no success.

The worst siege ever took place in 1678, when 15 000 Danes and Norwegians bombarded the 900 Swedish and Finnish defenders during two long summer months. Under the wire came Swedish reinforcement and the enemy had to retreat. Bohus was almost a ruin after the last siege and had to be restored.

Under the direction of the Swedish Castle-and fortification architect Erik Dahlberg, the demolished Renaissance Caste was rebuilt to serve as a fortress. There were no more sieges after 1678 and during the 18th century Bohus fortress mainly served as a state prison.

Demolition and restoration

The last Swedish garrison departed in 1786, but two years later the abandoned Bohus was used as a defense point by the Danish-Norwegian troops during the ”Theater War”. The Swedes eluded that war with mere terror, but understood that an unattended fortress could cause more harm than good. Therefore, in 1789, it was decided to dismantle Bohus fortress, with King Gustaf’s III approval.

An almost 500 year period as a defensive stronghold had come to an end. After the demolition was decided, the inhabitants of Kungälv were even allowed to retrive stones from the ruins, which were gratefully accepted. Stones from Bohus fortress can now be seen in grounds and walls of the old houses along the streets Västra gatan and Östra gatan in Kungälv.

In 1838, King Carl XIV forbade any further demolishion of Bohus fortress due to its cultural and historical value. At the turn of the century, in 1900, the first conservation works took place under the direction of Colonel Claes Grill and in 1925 the National Property Board took over the administration of Bohus fortress.

During the economic depression in 1934, the restoration works were carried out by unemployed men. In 1935 the Fortress was valued as an important cultural and historical heritage and became a state monument, protected by law.