Philadelphia served as the U.S. national capital from 1790 to 1800 before Washington, D.C.
The federal government moved from New York City to Philadelphia in 1790 under the Residence Act. Philadelphia was already a major political center: the Continental Congress had met there, the Declaration of Independence had been adopted there, and the Constitutional Convention had gathered at the Pennsylvania State House, now Independence Hall.
During the capital decade, Congress met at Congress Hall and President George Washington lived in the President’s House. Philadelphia was not intended to remain the permanent capital. The Residence Act selected a new federal district on the Potomac River, and the government moved there in 1800 as Washington, D.C., was being developed.
Philadelphia had also served as a revolutionary-era capital on several earlier occasions, including during the British occupation of New York City. New York City was the first capital under the Constitution from 1789 to 1790, while Washington, D.C., became the permanent national capital after the Philadelphia period.