Key Facts
- Date of action
- March 4, 1776
- British evacuation date
- March 17, 1776
- British destination
- Halifax, Nova Scotia
- Key weapon
- Cannons mounted on Dorchester Heights
- Foiled British response
- Counterattack prevented by snowstorm
Strategic Narrative Overview
On the night of March 4–5, 1776, Continental Army troops moved swiftly and quietly to occupy Dorchester Heights, erecting fortifications and emplacing cannons before dawn. The British garrison awoke to find the heights fortified and their ships in the harbor under direct threat. General Howe organized a counterattack to retake the heights, but a severe snowstorm on March 5 made the assault impossible to execute and he abandoned the plan.
01 / The Origins
By early 1776, the Continental Army had besieged British-occupied Boston for nearly a year following the outbreak of the American Revolutionary War. Washington sought a way to break the stalemate. Cannons captured at Fort Ticonderoga were hauled overland to Boston, providing the firepower needed to threaten British positions. Washington's plan was to seize the commanding high ground of Dorchester Heights, overlooking both the city and the harbor.
03 / The Outcome
With his position in Boston rendered untenable, Howe negotiated an informal agreement whereby British forces would not burn the city if allowed to withdraw unmolested. On March 17, 1776, British troops and Loyalists who had sheltered in Boston during the siege boarded ships and sailed to Halifax, Nova Scotia. The Continental Army entered Boston, ending the siege and handing the American cause a significant early strategic victory.
Belligerents & Mobilization Analysis
Side A
1 belligerent
George Washington.
Side B
1 belligerent
William Howe.
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.