it was really effective
After 1765, growing philosophical and political differences strained the relationship between Great Britain and its colonies. Patriot protests against taxation without representation followed the Stamp Act and escalated into boycotts, which culminated in 1773 with the Sons of Liberty destroying a shipment of tea in Boston Harbor. Britain responded by closing Boston Harbor and passing a series of punitive measures against Massachusetts Bay Colony. Massachusetts colonists responded with the Suffolk Resolves, and they established a shadow government which wrested control of the countryside from the Crown. Twelve colonies formed a Continental Congress to coordinate their resistance, establishing committees and conventions that effectively seized power.[44]
British attempts to disarm the Massachusetts militia in Concord led to open combat on April 19, 1775. Militia forces then besieged Boston, forcing a British evacuation in March 1776, and Congress appointed George Washington to command the Continental Army. Concurrently, the Americans failed decisively in an attempt to invade Quebec and raise insurrection against the British. On July 2, 1776, the Second Continental Congress voted for independence, issuing its declaration on July 4. Sir William Howe launched a British counter-offensive, capturing New York City and leaving American morale at a low ebb. However, victories at Trenton and Princeton restored American confidence. In 1777, the British launched an invasion from Quebec under John Burgoyne, intending to isolate the New England Colonies. Instead of assisting this effort, Howe took his army on a separate campaign against Philadelphia, and Burgoyne was decisively defeated at Saratoga in October 1777.
Burgoyne's defeat had drastic consequences. France formally allied with the Americans and entered the war in 1778, and Spain joined the war the following year as an ally of France but not as an ally of the United States. In 1780, the Kingdom of Mysore attacked the British in India, and tensions between Great Britain and the Netherlands erupted into open war. In North America, the British mounted a "Southern strategy" led by Charles Cornwallis which hinged upon a Loyalist uprising, but too few came forward. Cornwallis suffered reversals at King's Mountain and Cowpens. He retreated to Yorktown, Virginia, intending an evacuation, but a decisive French naval victory deprived him of an escape. A Franco-American army led by the Comte de Rochambeau and Washington then besieged Cornwallis' army and, with no sign of relief, he surrendered in October 1781.