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war1644

1644 naval battle of the Torstenson War

October 13, 1644

A Swedish-Dutch coalition defeated the Danish-Norwegian fleet at Fehmarn, shifting Baltic naval dominance during the Torstenson War.

Quick Facts

Year
1644
Category
war

Key Facts

Swedish-Dutch ships
37 ships with 875 guns total
Danish ships
17 ships with 448 guns
Prisoners taken
1,000
Danish ships captured
10, including largest three
Danish ships wrecked
2
Allied losses
2 fireships and 1 Dutch ship

By the Numbers

37
Swedish-Dutch ships
17
Danish ships
1,000
Prisoners taken
10
Danish ships captured

Location

Map of GermanyMap of GermanyGermany

Cause → Event → Consequence

Cause

The Torstenson War (1643–1645) pitted Sweden against Denmark-Norway over control of Baltic trade routes and Swedish exemption from the Sound Toll. Sweden sought to neutralize Danish naval power, assembling a large fleet supplemented by hired Dutch warships to challenge Danish supremacy at sea.

Event

On 13 October 1644, a combined Swedish-Dutch fleet of 37 ships engaged 17 Danish-Norwegian vessels northwest of the island of Fehmarn in the Baltic Sea. The allied force overwhelmed the Danes, killing Admiral Pros Mund and capturing 1,000 prisoners, including several senior officers. Ten Danish ships were captured and two wrecked, at minimal cost to the attackers.

Consequence

The defeat devastated the Danish-Norwegian fleet and undermined Denmark's capacity to contest Baltic waters. This naval loss contributed to Denmark's weakened position in subsequent peace negotiations, ultimately leading to the Treaty of Brömsebro in 1645, which forced Denmark to cede significant territories and privileges to Sweden.

Belligerents & Mobilization Analysis

Side A

2 belligerents

SwedenDutch Republic (hired)
Peak Mobilized Forces37
Forces vs Casualties ratio
0Mobilized

Side B

1 belligerent

Denmark-Norway
Peak Mobilized Forces17
Forces vs Casualties ratio
0Mobilized
Key Commanders

Pros Mund (killed), Ulfeldt (captured), Benjamin Grabov (captured), Von Jasmund (captured).

Total Casualties (all sides)
1,000
Outcome
Decisive Swedish-Dutch victory; 10 Danish ships captured, 2 wrecked, 1,000 prisoners taken

Timeline Context

Timeline around 16441644164116421643164516461647September to November 1644 siege of a castle in North Yorkshire, EnglandSkirmish between Danes and Dutch in Malacca, 16441644 siege during the Franco-Spanish War1644 battle in England; part of the First English Civil War1644 battle between the Polish-Lithuanian Commonwealth and a horde of Crimean Tatars1644 English Civil War battleBattle that took place during the First English Civil War1644 rebellion in Beijing, China which deposed the Ming dynastybattle-of-fehmarn-1644