The American patriots were defeated at the Battle of Bunker Hill, but they proved they could hold their own against the superior British Army. The fierce fight confirmed that any reconciliation between England and her American colonies was no longer possible.

The battle was a tactical victory for the British, but it was a sobering experience. The British sustained twice as many casualties as the Americans and lost many officers. After the engagement, the patriots retreated and returned to their lines outside the perimeter of Boston.

British Commander-in-Chief General Sir Thomas Gage was under pressure to quash the colonial rebellion. By June, he had reinforcements and was ready to implement a new strategy. The British Army planned to launch an attack against the Americans on the heights north and south of Boston.

Details of the attack were leaked, however, and a detachment of 1,000 Massachusetts and Connecticut soldiers—more of an armed mob than a military unit—gathered to defend a hill in Charlestown. Among the defenders were several enslaved and free African Americans as well. The violent clash of these forces signaled that the colonial revolt would not be easily extinguished.