Battle of Lexington, brief skirmish that marked the first military clash in the American Revolution (1775-1783). It took place on April 19, 1775, between some 70 colonial minutemen commanded by Captain John Parker, and about 700 British soldiers marching on Concord, Massachusetts, under the command of Lieutenant Colonel Francis Smith. The American militia, warned of the British approach by the patriot Paul Revere and others, had assembled to halt the British. Inspired by the words of Captain Parker: “Stand your ground; don't fire unless fired upon, but if they mean to have a war, let it begin here,” the Americans refused to disperse when ordered to do so by the commander of the British advance units. Gunfire was exchanged and eight Americans were killed before the minutemen retreated. The Battle of Concord ensued (see Concord, Battle of).