What event triggered general war between Great Britain and its American colonies?

By late l774, provisional governments, some known as Committees of Safety, assumed control over governmental duties in a number of colonies. These provisional governments called for local militias to arm and train. In September 1774, British General Thomas Gage, the new military governor of Massachusetts, seized the munitions stored at Charles Town and Cambridge and also began to fortify his position in the city of Boston. Patriot spies, like Paul Revere in Boston, began to report on British troop movements to keep colonial munitions safe from seizure and keep rebel leaders from being arrested. The British seizure of gunpowder and munitions was countered by patriots who seized gunpowder from Fort William and Mary at New Castle, New Hampshire, in December 1774.

Battle of Lexington, illustration from Recueil d’Estampes Representant Les Differents Evenemens de la Guerre qui a Procure l’Independancey, 1784, Jamestown-Yorktown Foundation.

Battle of Lexington, illustration from Recueil d’Estampes Representant Les Differents Evenemens de la Guerre qui a Procure l’Independancey, 1784, Jamestown-Yorktown Foundation.

Parliament declared Massachusetts in a state of rebellion in February 1775 and authorized General Gage to use force to put down the rebellion. On April 14, 1775, General Gage received orders from the British government to disarm and arrest rebel leaders. British troops left Boston on the night of April 18, 1775, to seize the munitions stored by the patriots in Concord. Patriot spies gave warning of the movement of British troops, and minutemen assembled along the road from Boston to Lexington. The conflict the next day between the British soldiers and the New England minutemen in Lexington was the spark which led to general war. Coincidentally, the day after the Battles of Lexington and Concord, the Royal Governor of Virginia seized the gunpowder stored in the magazine in Williamsburg. An angry mob descended on the Governor’s Palace in Williamsburg, demanding the return of the gunpowder. Calmer heads prevailed and violence was averted. The British government had decided it was time to take decisive action to end the growing rebellion.

Shortly after the Battles of Lexington and Concord and the gunpowder incident in Williamsburg, the second Continental Congress reconvened in Philadelphia and learned British forces in Boston were under siege by thousands of New England minutemen. This Congress authorized the creation of the Continental Army and, on June 15, 1775, appointed George Washington commander of the American forces. Washington’s selection reflected his reputation as a veteran of the French and Indian War, as well as his position as one of Virginia’s most powerful men