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The Battles of Lexington and Concord were the opening engagements of the American Revolution. While marching from Boston to Concord to seize colonists' military stores, a British force of 700 was met at Lexington by 77 local minutemen. After a brief exchange of shots, the outnumbered colonists fell back. The British continued on to Concord, where they were defeated by a militia of about 500.
Who had been sent to warn the people of the Massachusetts countryside about the impending British attack?
Source: Battles of Lexington and Concord (1775) (http://encyclopedia.thefreedictionary.com/Battles+of+Lexington+and+Concord)