New York City served as the first capital of the United States under the Constitution.
The federal government began operating under the Constitution in 1789, and New York City became the national capital that same year. Federal Hall on Wall Street hosted George Washington’s inauguration as the first president on April 30, 1789.
The capital moved to Philadelphia in 1790 under the Residence Act. Philadelphia remained the temporary capital while a permanent site was developed on the Potomac River.
Washington, D.C., became the permanent capital in 1800. New York City therefore was not the first capital in every sense: earlier revolutionary governments used other locations, including Philadelphia and Baltimore. The question specifically concerns the first capital under the Constitution’s new federal government.