On March 2, 1776, General George Washington orders American artillery forces to begin bombarding Boston from their positions at Lechmere Point, northwest of the city center—in advance of bringing in the big guns. It marked the beginning of the end of the Siege of Boston and Britain's wartime occupation of Boston.
After two straight days of bombardment, American Brigadier General John Thomas slipped 2,000 troops, cannons and artillery into position just south of Boston at Dorchester Heights. The 59 cannons had been transported 300 miles—a strenuous trip at the height of a New England winter—by bookseller-turned-Patriot Henry Knox from Fort Ticonderoga, where they had been recently captured by Lieutenant Colonel Benedict Arnold and Ethan Allen with his Green Mountain Boys.
By March 5, 1776, the Continental Army had artillery troops in position around Boston, including the elevated position at Dorchester Heights, overlooking the city. British General William Howe realized Boston was indefensible to the American positions and decided, on March 7, 1776, to leave the city. Ten days later, on March 17, 1776, the eight-year British occupation of Boston ended when British troops evacuated the city and sailed to the safety of Halifax, Nova Scotia.
The victory at Boston resulted in John Thomas’ promotion to major general; soon after, he was assigned to replace General Richard Montgomery, who was killed in action as he and Benedict Arnold attempted to take Quebec. Thomas arrived at Quebec on May 1 and soon lost his own life. Although a physician by profession, he died of smallpox on June 2, as the Patriots retreated up the Richelieu River from their failed siege of the city.
