The Panic of 1819 initiates a major economic recession. Prosperity returns in 1824.

On August 1, construction commences on the Cumberland Road linking Maryland to the Midwest. Construction stops at Vandalia, Illinois in 1838 when funding runs out.

On January 1, the United States terminates its participation in the international slave trade.

On June 15, the Twelfth Amendment to the Constitution, which reorders the presidential selection process, becomes law with its ratification by New Hampshire.