HistoryData
Historical ConflictVincennes

Siege of Fort Vincennes

Clark's capture of Fort Sackville secured the Old Northwest for the United States and weakened British frontier control during the Revolutionary War.

Duration & Scope

1779 ongoing

< 1 year

Key Facts

Date
February 1779
Theater
American Revolutionary War frontier
American commander
Lt. Col. George Rogers Clark
British commander
Lt. Gov. Henry Hamilton
Departure point of march
Kaskaskia, Illinois

Strategic Narrative Overview

Lieutenant Colonel George Rogers Clark led a daring winter march of American militia from Kaskaskia through flooded lowlands, covering roughly 180 miles in harsh February conditions. Arriving at Vincennes, Clark's force surprised the garrison. To intimidate Hamilton and signal resolve to local Native American observers, Clark ordered the public execution of four Odawa captives taken during the approach. This act, combined with the unexpected appearance of the American force, broke British and allied morale.

01 / The Origins

During the American Revolutionary War, Britain maintained frontier posts across the Old Northwest, relying on Native American allies and small garrisons to hold the region. Fort Sackville at Vincennes was a key British stronghold commanded by Lieutenant Governor Henry Hamilton, known to colonists as the 'Hair-Buyer.' American control of the interior was tenuous, and the British had retaken Vincennes from American hands in late 1778, threatening patriot settlements along the frontier.

03 / The Outcome

Faced with a determined enemy and collapsing Native American support, Lieutenant Governor Henry Hamilton surrendered Fort Sackville to Clark in February 1779. Hamilton was taken prisoner and sent to Virginia. The American victory extended patriot influence deep into the Old Northwest and contributed to the eventual cession of the region to the United States in the 1783 Treaty of Paris, denying Britain a buffer territory north of the Ohio River.

Belligerents & Mobilization Analysis

Side A

1 belligerent

American Militia (Virginia)
Key Commanders

George Rogers Clark.

Side B

1 belligerent

British Garrison (Fort Sackville)
Key Commanders

Henry Hamilton.

Outcome
American victory; British garrison under Hamilton surrendered; Fort Sackville captured by Clark's militia

Kinetic Engagement Axis

Major engagements timeline (1779–present)Timeline of major military engagements plotted chronologically.1779present1779Siege of Fort Sa…Allied

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of Vincennes, United StatesMap of Vincennes, United StatesVincennes, United States