"Battle of Lexington" - British troops fire on colonists, who had gathered at Lexington to stop them from going on to Concord to destroy a colonial supply depot. Major Pitcairn, the British officer on horseback, had ordered the colonists to disarm and disperse. As they began to do so, a single shot was fired, which led to an exchange of fire between a British platoon and the colonial militia. Eight militiamen were killed and ten wounded before Pitcairn regained control of his troops. Thus the American Revolution started, with "the shot heard round the world."