Which 1775 battles marked the first major fighting of the American Revolutionary War?

The Battles of Lexington and Concord marked the first major fighting of the American Revolutionary War on April 19, 1775.

British troops marched from Boston toward Concord to seize colonial military supplies. Colonial militiamen confronted them at Lexington, where the first exchange of fire occurred, and resistance continued during the British retreat through Concord and surrounding communities.

The fighting caused casualties on both sides and brought thousands of Massachusetts militia members toward Boston. The engagement transformed a political crisis into an open war between colonial forces and the British army.

The phrase “shot heard round the world” later became associated with the opening clash at Lexington Green. The exact identity of the first person to fire remains uncertain, so the battles—not a named individual—are the canonical answer.