March 17 is more known for that other holiday where everything is green. You night not be celebrating today if it were not for the events of 1776.
In 1776, British forces had occupied Boston for years. The local militia and Continental army had been harassing the British soldiers, leaving them isolated on the small peninsula that was Boston at the time.
In May of 1775 American forces had captured Fort Ticonderoga on Lake Champlain and its artillery. Colonel Henry Knox, Washington’s chief of artillery, suggested to General Washington that they bring the captured artillery to Boston. Knox and his men hauled tons of artillery over the rugged Berkshires, through swamps and along crude roads, for 300 miles.
Washington first placed some of the heavy cannons in Cambridge and Roxbury. They were effective to harass the British, but were merely a diversion. The batteries opened fire on the night of March 2. The British returned fire, without significant casualties on either side. The action was repeated on March 3.
It was repeated again on March 4. But this night was the true diversion. Troops marched to the top of Dorchester Heights hauling tools and cannon placements. Throughout the night the troops built earthworks overlooking Boston and the harbor. The artillery was in place to controll access to the city.
On the morning of March 5, the British saw the fortifications. It was a key date because March 5 was the sixth anniversary of the Boston Massacre.
Washington controlled the harbor and access by land to the Boston peninsula. The British were vulnerable and had to either flee or try to take back Dorchester Heights. British General Howe decided to preserve his army for battle elsewhere rather than attempt to hold Boston. Howe informed Washington that Boston would not be burned if his troops were allowed to leave unmolested.
After several days of preparation and several days of delay caused by bad weather, the British forces departed Boston on March 17 and sailed to Halifax. Hundreds of 1,000 loyalist fled Boston with the troops, afraid of the rebel forces.
This was the first major victory of the Revolutionary War. The citizens of Boston were not willing to comply with the British mandates. A city full of British soldiers was causing trouble, even for those were not keen on the rebellion.
Evacuation Day was declared a city holiday in 1901. The state made it a holiday in Suffolk County in 1938. Perhaps the large Irish population of Boston played a role in the establishment of the holiday that coincided with St. Patrick’s Day.
As you hoist a green beer today, remember this victory.