What city was the first national capital under the United States Constitution?

New York City was the first national capital under the United States Constitution.

When the new federal government began operating in 1789, Congress met in New York City at Federal Hall on Wall Street. George Washington was inaugurated there on April 30, 1789, becoming the first president under the Constitution. The city therefore served as the seat of the new national government during its earliest months.

The capital later moved to Philadelphia in 1790 under the Residence Act. Philadelphia remained the capital for a decade, while plans proceeded for a permanent federal district on the Potomac River. The government moved to Washington, D.C., in 1800.

New York City is sometimes overlooked because Washington, D.C., has been the permanent capital since 1800 and Philadelphia had served as a revolutionary-era center. The question concerns the first capital under the Constitution, not the first meeting place of the Continental Congress or the location where the Declaration of Independence was adopted.