Lancaster, Pennsylvania — home to James Buchanan, Jr., the 15th president of the United States, and to congressman, abolitionist and “Radical Republican” Thaddeus Stevens — served, during the American Revolution, as the capital of the United States for one day, on September 27, 1777.
This occurred after the Continental Congress fled Philadelphia, which had been captured by the British. The revolutionary government then moved still further away, to York.