Qualla: Siege of Bohus Fortress (1678)

Siege of Bohus Fortress (1678): Introduction

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit Bohus1678.jpg: Anonym derivative work: Dagjoh (talk), Public domain. Anyone who spoke of surrender was to be executed as a traitor. That was the order given to the 400 Swedish soldiers garrisoned inside Bohus Fortress in the summer of 1678, as they stared down at an approaching army of 15,000 Dano-Norwegian troops under General Ulrik Frederik Gyldenløve. The odds were impossible, the outcome seemingly certain. Yet for weeks, this battered medieval fortress on the Swedish-Norwegian border would become the site of one of Scandinavia's most stubborn defensive stands.

Image: Bohus1678.jpg: Anonym derivative work: Dagjoh (talk) | Public domain

Siege of Bohus Fortress (1678): Echoes of Continental Conflict

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit AnonymousUnknown author, Public domain. The siege of Bohus was a distant consequence of France's ambitions in the Low Countries. In 1672, Louis XIV had turned his expansionist gaze toward the Netherlands, drawing European powers into a web of alliances and counter-alliances. Sweden, its treasury empty and Denmark perpe...

Image: AnonymousUnknown author | Public domain

Siege of Bohus Fortress (1678): The Walls Hold

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit Erik Dahlberg, Public domain. The bombardment began almost immediately, and it was devastating. The garrison commanders, Fredrich von Börstell and Carl Gustaf Fröhlich, watched helplessly as their defenses crumbled. By June 17, the Blockhouse and the "Alarm Place" lay in ruins. The outer works had been system...

Image: Erik Dahlberg | Public domain

Siege of Bohus Fortress (1678): The Bridge and the Fire

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit Erik Dahlberg, Public domain. The Dano-Norwegians attempted to build a bridge from Hisingen Island to the fortress, seeking to tighten their stranglehold. Börstell launched a counterattack and burned it. Though the besiegers eventually repaired the crossing and advanced toward Skarpenort, the Swedish defender...

Image: Erik Dahlberg | Public domain

Siege of Bohus Fortress (1678): Night Crossing

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit Erik Dahlberg, Public domain. On July 18, Stenbock began his march toward Bohus with an army of 12,000 men. He constructed a bridge to Hisingen, protected by armed barges and pontoon bridges. Under cover of darkness on the night of July 18-19, the entire Swedish army crossed to the island. At dawn, Stenbock s...

Image: Erik Dahlberg | Public domain

Siege of Bohus Fortress (1678): Relief and Ruin

Tue, 03 Feb 2026 00:00:00 GMT

Photo credit Erik Dahlberg, Public domain. The Danes at Gullön had built fortifications and a bridge to communicate with the mainland, but the approaching Swedish army was overwhelming. On the night of July 22, the Swedes forced them to retreat, systematically destroying their fortifications, bridges, and camp. The next d...

Image: Erik Dahlberg | Public domain