The presidency before George Washington
Before the official office of the president the officials that made decisions for the country were know and the continental congress. As such, the president of the Continental Congress was a position with limited authority. The Continental Congress, not wanting to authorize political power in an individual, gave their presiding officer even less responsibility than the speakers in the lower houses of the colonial assemblies. The president of Congress could not, set the legislative agenda or make committee appointments, could not meet privately with foreign leaders; such meetings were held with committees or the entire Congress.
The First Continental Congress met in Carpenters' Hall, Philadelphia from September 5 to October 26, 1774. The presidency was a largely ceremonial position and was not a paid position. The main role of the office was to preside over meetings of Congress, which required serving as an impartial moderator during debates. When Congress would form a committee to discuss important matters, the president would give up his chair to the chairman of that committee. A problem arose, when President Thomas McKean was at the same time serving as Chief Justice of Pennsylvania, provoked some criticism that he had become too powerful.
The president was a member of Congress elected by the other delegates to serve as a neutral discussion moderator during meetings of Congress. Designed to be a largely ceremonial position without much influence, the office was unrelated to the later office of President of the United States. The president was also responsible for dealing with a large amount of official correspondence, but he could not answer any letter without being instructed to do so by Congress. Presidents also signed, but did not write, Congress's official documents. These limitations could be frustrating, because a delegate essentially declined in influence when he was elected president.
During the time of the Revolutionary War, the President presided over the Continental Congress. And then President John Hancock was the first person to sign the Declaration of Independence. After the Articles of Confederation were ratified, the President presided over its Congress. President Thomas Mifflin accepted General George Washington's resignation of his commission. Washington would then later become President of the Constitutional Convention and from there the first President under the Constitution.