<P> In response, the colonies formed bodies of elected representatives known as Provincial Congresses, and Colonists began to boycott imported British merchandise . Later in 1774, 12 colonies sent representatives to the First Continental Congress in Philadelphia . During the Second Continental Congress, the remaining colony of Georgia sent delegates, as well . </P> <P> Massachusetts Governor Thomas Gage feared a confrontation with the colonists; he requested reinforcements from Britain, but the British government was not willing to pay for the expense of stationing tens of thousands of soldiers in the Thirteen Colonies . Gage was instead ordered to seize Patriot arsenals . He dispatched a force to march on the arsenal at Concord, Massachusetts, but the Patriots learned about it and blocked their advance . The Patriots repulsed the British force at the April 1775 Battles of Lexington and Concord, then lay siege to Boston . </P> <P> By spring 1775, all royal officials had been expelled, and the Continental Congress hosted a convention of delegates for the 13 colonies . It raised an army to fight the British and named George Washington its commander, made treaties, declared independence, and recommended that the colonies write constitutions and become states . The Second Continental Congress assembled in May 1775 and began to coordinate armed resistance against Britain . It established a government that recruited soldiers and printed its own money . General Washington took command of the Patriot soldiers in New England and forced the British to withdraw from Boston . In 1776, the Thirteen Colonies declared their independence from Britain . With the help of France and Spain, they defeated the British in the American Revolutionary War . In the Treaty of Paris (1783), Britain officially recognized the independence of the United States of America . </P> <Table> Population of the American colonies <Tr> <Th> Year </Th> <Th> Population </Th> </Tr> <Tr> <Th> 1625 </Th> <Td> 1,980 </Td> </Tr> <Tr> <Th> 1641 </Th> <Td> 50,000 </Td> </Tr> <Tr> <Th> 1688 </Th> <Td> 200,000 </Td> </Tr> <Tr> <Th> 1702 </Th> <Td> 270,000 </Td> </Tr> <Tr> <Th> 1715 </Th> <Td> 435,000 </Td> </Tr> <Tr> <Th> 1749 </Th> <Td> 1,000,000 </Td> </Tr> <Tr> <Th> 1754 </Th> <Td> 1,500,000 </Td> </Tr> <Tr> <Th> 1765 </Th> <Td> 2,200,000 </Td> </Tr> <Tr> <Th> 1775 </Th> <Td> 2,400,000 </Td> </Tr> </Table>

Who did the 13 colonies declared independence from