HistoryData
Historical ConflictFredriksten

Siege of Fredriksten

Charles XII of Sweden was killed during the siege, ending Swedish imperial ambitions and triggering the Age of Liberty in Sweden.

Duration & Scope

1718 ongoing

< 1 year

Estimated Total Casualties

209

Key Facts

Year
1718
Notable death
King Charles XII of Sweden killed
Result
Swedish siege abandoned; Norwegians held fortress
Fortress
Fredriksten, Fredrikshald (now Halden)
Recorded casualties
209

Strategic Narrative Overview

Swedish forces under Charles XII besieged the Norwegian fortress of Fredriksten in the city of Fredrikshald. While inspecting his troops' forward lines, Charles XII was struck and killed by a projectile — the circumstances of which, whether enemy fire or assassination, have long been debated. His death abruptly halted Swedish offensive momentum and left the army without decisive leadership.

01 / The Origins

The siege of Fredriksten took place during the Great Northern War, in which Sweden under Charles XII contested dominance of northern Europe against a coalition of powers. By 1718, Sweden's position had weakened considerably after the disastrous Russian campaign, but Charles XII pressed forward with an invasion of Norway, targeting the fortress of Fredriksten as a strategic objective to strengthen his negotiating position.

03 / The Outcome

Following the death of Charles XII, the Swedish forces abandoned the siege and withdrew, leaving the Norwegians in full control of Fredriksten. The king's death effectively ended Sweden's imperial ambitions. Combined with the Treaty of Nystad in 1721, which concluded the Great Northern War, it ushered in the Age of Liberty in Sweden, shifting power from the monarchy to the Swedish parliament.

Belligerents & Mobilization Analysis

Side A

1 belligerent

Swedish Empire
Key Commanders

Charles XII of Sweden.

Side B

1 belligerent

Norway (Denmark-Norway)
Total Casualties (all sides)
209
Outcome
Swedish siege abandoned after Charles XII killed; Norwegians retained Fredriksten fortress

Kinetic Engagement Axis

Major engagements timeline (1718–present)Timeline of major military engagements plotted chronologically.1718present1718Siege of Fredrik…Side B

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of Halden, NorwayMap of Halden, NorwayHalden, Norway