The Battles of Lexington and Concord were the first military engagements of the American Revolutionary War. The battles were fought on April 19, 1775 in Middlesex County, Province of Massachusetts Bay, within the towns of Lexington, Concord, Lincoln, Menotomy (present-day Arlington), and Cambridge. They marked the outbreak of armed conflict between the Kingdom of Great Britain and its thirteen colonies in America.

In late 1774, Colonial leaders adopted the Suffolk Resolves in resistance to the alterations made to the Massachusetts colonial government by the British parliament following the Boston Tea Party. The colonial assembly responded by forming a Patriot provisional government known as the Massachusetts Provincial Congress and calling for local militias to train for possible hostilities. The Colonial government exercised effective control of the colony outside of British-controlled Boston. In response, the British government in February 1775 declared Massachusetts to be in a state of rebellion.

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