The significance of the Battle of Lexington and Concord, fought on April 19, 1775, lies in its role as the opening confrontation of the American Revolutionary War. These battles marked the first military engagements between colonial militias and British forces, representing a pivotal shift from political tension to armed conflict. As the "shot heard 'round the world," the events galvanized support for independence among the colonies and initiated an organized rebellion against British rule. The battles symbolized the American spirit of resistance and the quest for self-determination.