HistoryData
Historical ConflictFort Stanwix

Siege of Fort Stanwix

The failed British siege forced St. Leger's withdrawal, denying Burgoyne a western flank and contributing to the American victory at Saratoga.

Duration & Scope

1777 ongoing

< 1 year

Key Facts

Duration
August 2–22, 1777 (20 days)
Garrison commander
Colonel Peter Gansevoort
Besieging commander
Brigadier General Barry St. Leger
Key related battle
Battle of Oriskany, August 6, 1777
Strategic purpose
Diversion for Burgoyne's Hudson River Valley campaign

Strategic Narrative Overview

St. Leger's mixed force of British regulars, Loyalists, Hessians, and Indigenous warriors began besieging Fort Stanwix on August 2. A relief column under Brigadier General Nicholas Herkimer was ambushed at the Battle of Oriskany on August 6, though the fort's garrison sortied and plundered enemy camps, damaging Indigenous morale. Major General Benedict Arnold then advanced with reinforcements, using a deception to inflate his apparent troop strength, causing many Indigenous warriors to abandon the siege.

01 / The Origins

During the American Revolutionary War, British Lieutenant General John Burgoyne planned a multi-pronged campaign to seize the Hudson River Valley and isolate New England. Brigadier General Barry St. Leger was tasked with advancing eastward through the Mohawk Valley from Lake Ontario as a diversionary western thrust, requiring him to neutralize Fort Stanwix, the Continental Army's key defensive position guarding the valley's western approaches.

03 / The Outcome

Undermined by Arnold's ruse and the erosion of his Indigenous allies, St. Leger abandoned the siege on August 22 and withdrew. His failure to advance on Albany left Burgoyne's western flank unsupported. Although St. Leger reached Fort Ticonderoga in late September, it was too late to assist Burgoyne, who surrendered at Saratoga in October 1777, a turning point of the Revolutionary War.

Belligerents & Mobilization Analysis

Side A

1 belligerent

British regulars, Loyalists, Hessians, and Indigenous warriors
Key Commanders

Barry St. Leger.

Side B

1 belligerent

Continental Army (New York and Massachusetts)
Key Commanders

Peter Gansevoort, Nicholas Herkimer, Benedict Arnold.

Outcome
American defensive victory; St. Leger withdrew after Arnold's deception and Indigenous desertion

Kinetic Engagement Axis

Major engagements timeline (1777–present)Timeline of major military engagements plotted chronologically.1777present1777Battle of OriskanyInconclusive

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of Rome, United StatesMap of Rome, United StatesRome, United States