On the evening of March 5, 1770, Crispus Attucks, a 47-year-old man of mixed African and Native American descent who worked as a sailor and ropemaker, was killed in Boston, Massachusetts during a confrontation between colonists and British soldiers outside the Custom House on King Street. A dispute between a young apprentice and a British officer escalated into a crowd throwing snowballs, ice, and sticks at a sentry; reinforcements led by Captain Thomas Preston and seven soldiers of the 29th Regiment of Foot formed a defensive line and, after one soldier was struck, a volley of shots was fired into the crowd.

Attucks was the first to fall, struck by two musket balls in the chest; four other men also died in what became known as the Boston Massacre. Captain Preston, eight soldiers, and four civilians were arrested and charged with murder; John Adams defended the soldiers at trial.

Preston and six soldiers were acquitted, while two soldiers, Hugh Montgomery and Matthew Kilroy, were convicted of manslaughter, branded on the thumb, and released.