British Forces Evacuate Boston

Context

By early 1776, Boston had endured nearly eight years of British military presence that began when redcoats arrived in 1768 to enforce parliamentary authority. Tensions had escalated through the Boston Massacre of 1770 and the occupation of the city following the battles at Lexington and Concord in April 1775. The Continental Army, commanded by George Washington since June 1775, settled into a prolonged siege that bottled up roughly 10,000 British troops and their naval support inside the harbor.

What Happened

In late February and early March, Washington ordered the secret movement of heavy artillery captured at Fort Ticonderoga the previous spring. On the night of March 4, Brigadier General John Thomas led 800 soldiers and 1,200 laborers up Dorchester Heights south of the city. Working through the night under cover of a diversionary bombardment, they erected fortifications and emplaced the guns by morning. British General William Howe prepared a counterattack but abandoned the plan when a severe storm struck on March 5. Recognizing that the new American position dominated the harbor and rendered the British fleet vulnerable, Howe chose evacuation over another costly assault like Bunker Hill.

Aftermath

On March 17 the British began loading troops, supplies, and civilian Loyalists onto a fleet of more than 100 vessels. Roughly 11,000 soldiers and about 1,000 Loyalists departed for Halifax, Nova Scotia, leaving behind spiked cannons, wagons, and stores valued at tens of thousands of pounds. American forces entered the city the following day to scenes of jubilation mixed with the debris of hasty departure. Washington received the first congressional gold medal for the bloodless victory.

Legacy

The evacuation marked the first clear strategic success for the Patriot cause and demonstrated that Washington could compel a professional army to withdraw without a decisive battle. It freed Boston from occupation, lifted morale across the colonies, and allowed the Continental Army to shift focus southward. Boston still observes Evacuation Day each March 17, and the episode remains a textbook example of the value of terrain and artillery in Revolutionary War strategy.