Events from the year 1822 in the United States.
- President: James Monroe (DR-Virginia)
- Vice President: Daniel D. Tompkins (DR-New York)
- Chief Justice: John Marshall (Virginia)
- Speaker of the House of Representatives: Philip P. Barbour (DR-Virginia)
- Congress: 17th
- March 30 – The U.S. merges East Florida with part of West Florida to form the Florida Territory.
- July 1–3 – U.S. House of Representatives elections begin in Louisiana and continue until the last elections are held in North Carolina on August 14, 1823.
- July 2 – Denmark Vesey is hanged for plotting a slave rebellion in Charleston, South Carolina.
- July 4 – A 24th star is added to the flag of the United States, representing Missouri which had been admitted on August 10, 1821.
- August 22 – The English ship Orion lands at Yerba Buena, modern-day San Francisco, under the command of William A. Richardson.
- November 9 – Action of 9 November 1822: USS Alligator (1820) engages three pirate schooners off the coast of Cuba as part of the West Indies anti-piracy operations of the U.S.
- November 23 – The USS Alligator wrecks on Carysford Reef off the coast of Florida.
- December 5 – Edward Coles is inaugurated as the second governor of Illinois, Preceding Shadrach Bond.
- Ashley's Hundred leave from St. Louis, setting off a major increase in fur trade.
- A committee is formed to collect remains from the remote location where the Battle of Minisink had been fought in 1779.
- The last major outbreak of yellow fever in New York City occurs.
- Gist Mansion is built in Wellsburg, West Virginia (used some 100 years later for the Brooke Hills Spooktacular).
- Era of Good Feelings (1817–1825)
- February 4 – Edward Fitzgerald Beale, U.S. Navy lieutenant and explorer (died 1893)
- February 13 – James B. Beck, Scottish-born U.S. Senator from Kentucky from 1877 to 1890 (died 1890)
- c. March – Harriet Tubman, born Araminta Ross, African-American abolitionist, humanitarian, and Union spy during the American Civil War (died 1913)
- March 12 – Thomas Buchanan Read, poet and portrait painter (died 1872)
- March 16 – John Pope, career United States Army officer and Union general in the American Civil War (died 1892)
- April 3 – Edward Everett Hale, writer (died 1909)
- April 26 – Frederick Law Olmsted, landscape architect (died 1903)
- April 27 – Ulysses S. Grant, 18th President of the United States from 1869 to 1877 (died 1885)
- May 18 – Mathew B. Brady, pioneer photographer (died 1896)
- June 10 –
- July 21 – Alexander H. Jones, Congressional Representative from North Carolina. (died 1901)
- July 25 – Andrew Bryson, admiral (died 1892)
- August 15
- August 27 – William Hayden English, politician (died 1896)
- September 11 – Francis S. Thayer, merchant and politician (died 1880)
- September 16 – Charles Crocker, financiers (died 1888)
- September 17 – Cornelius Cole, U.S. Senator from California from 1867 to 1873 (died 1924)
- September 19 – Joseph R. West, U.S. Senator from Louisiana from 1871 to 1877 (died 1898)
- September 20 – Elizabeth Smith Miller, women's rights campaigner (died 1911)
- October 4 – Rutherford B. Hayes, 19th President of the United States from 1877 to 1881 (died 1893)
- Undated – Red Cloud (Maȟpíya Lúta), Oglala Lakota chief (died 1909)
- April 8 – James Long, US Filibuster, founder of the Long Republic - the first "Republic of Texas". Shot by a prison guard in Mexico City, Mexico (born 1793).
- May 6 – Charles Peale Polk, portrait painter (born 1767)
- May 8 – John Stark, major general in the Continental Army during the American Revolution (born 1728)
- July 2 – Denmark Vesey, African American leader, hanged (born c.1767)
- August 28 – William Logan, U.S. Senator from Kentucky from 1819 to 1820 (born 1776)
- October 31 – Jared Ingersoll, U.S. presidential candidate (born 1749)
- Media related to 1822 in the United States at Wikimedia Commons