The American colonies declared their independence from Great Britian in 1776. Under the leadership of General Washington, those states actually won that independence in 1783 with the signing of the Treaty of Paris. At the close of the war, Washington circulated a letter to the governors of the thirteen newly independent states, now governed under the Articles of Confederation. That letter was to be Washington's public farewell. He was disbanding the Continental army and stepping down from his position at the head of it. In the letter he provided detailed advice regarding the governing of the new nation, but he was not expressing any desire to be a part of that government. He had no intention of becoming the first President of the United States because that position did not exist.
But the Articles of Confederation, it turned out, represented a fairly poor framework for government. The Constitutuonal Convention was convened in 1787 to create something better. The delegates present agreed that the new government needed some type of centralized federal authority, with a single executive at its helm, but, fearing the potential for tyrany investing so much power in one individual, they devised checks and balances to ensure that the President would never become yet another king.
George Washington was chosen as the very first to assume the newly created office of president. He was unanimously elected to that office in January, 1789. He would serve two terms and then step down once again from public life in 1797, this time for good. Washington set a precedent by serving only two terms, a tradition that remained in effect until Franklin Roosevelt ran for and won a third term in office. (The 22nd Amendment, passed shortly after Roosevelt's death, now allows for a president to serve only two terms.)
Washington was the only U.S. President who never lived in the White House. In 1800, 2nd U.S. President John Adams moved in to 1600 Pennsyvania Ave in Washington, DC. For the beginning of Adam's presidency and all of Washington's, the official residence of the president was in Philadelphia. The President's House in Philadelphia is now a national historic landmark, administered by the National Park Service. The establishment of this historic site was surrounded by considerable controversy, as Washington kept slaves on the grounds of the first executive mansion.
The Consitutuion set up a framework for a representative democratic republic that had no real historical precedent. Washington proved an able pioneer in this unexplored political territory, his administration overseeing the establishment of a national banking system and settling the enormous debts incurred by the Revolution. Washington is widely regarded as one of our very greatest presidents, and is considered by many "The Father of our Country."