The Continental Congress
The Stamp Act Congress, formed by colonials to respond to the unpopular Stamp Act taxes, was the direct precursor of the Continental Congress, which was itself formed largely in response to the so-called "Intolerable Acts". The First Continental Congress was planned through the permanent committees of correspondence, which kept the local colonial governments in communication with one another as their common opposition to Britain grew. It lasted only from September 5, 1774, to October 26, 1774, in Philadelphia, Pennsylvania. Peyton Randolph served as the first President of the Continental Congress.
The primary accomplishment of the First Continental Congress was the drafting of the Articles of Association on October 20. The Articles formed a compact among twelve of the thirteen colonies to boycott British goods, and to cease exports to Britain as well if the "Intolerable Acts" were not repealed. The boycott was successfully implemented, but its potential at altering British colonial policy was cut off by the outbreak of open fighting in 1775.
The Second Continental Congress met on May 10, 1775. The Congress resolved that Britain had declared war against them on March 26 of that year. The Continental Army was created on June 15 to oppose the British, and General George Washington was appointed commander in chief. On July 8 they extended the Olive Branch Petition to the crown as an attempt at reconciliation (King George III refused to receive it). Silas Deane was sent to France as an ambassador of the United States. American ports were reopened in defiance of the Navigation Acts. Most importantly, on July 7, 1776, they adopted the Declaration of Independence. This Congress nobly tried to lead the new country through the war with very little money and little real power. The Congress had disagreements with others such as politicians who wanted payment and the military who wanted more control.
At the end of the War, in 1783, disagreements between the members of the Congress lead to the formal close of the congress: each of the United States of America would follow their own paths and alliances from now on.