Final answer:
The American militiamen who were ready to fight at a minute's notice were known as Minutemen, forming a key part of the early Revolutionary War efforts.
Step-by-step explanation:
American militiamen who volunteered to be ready for service at a minute's notice during the Revolutionary War were known as Minutemen. These individuals formed an elite arm of the colonial militia, particularly following the tension resulting from the Tea Party of December 1773. The Minutemen played a critical role in the early stages of the American Revolutionary War, especially noted for their rapid mobilization during key moments, such as the battles at Lexington and Concord. They were an elite arm of the colonial militia during the American Revolution, formed in response to the tension following the Boston Tea Party. The Minutemen were ready to assemble and engage in military action very quickly, hence their name.