The first battle of the Revolutionary War, fought in Massachusetts on April 19, 1775. British troops had moved from Boston toward Lexington and Concord to seize the colonists' military supplies and arrest revolutionaries. In Concord, advancing British troops met resistance from the Minutemen, and American volunteers harassed the retreating British troops along the Concord-Lexington Road. Paul Revere, on his famous ride, had first alerted the Americans to the British movement.
Note: During the battle there was a skirmish at Concord's North Bridge, later commemorated in a poem by Ralph Waldo Emerson:
By the rude bridge that arched the flood,
Their flag to April's breeze unfurled,
Here once the embattled farmers stood
And fired the shot heard round the world.