- 1821 James Monroe takes oath on Mar 4 for second term of Presidency.
- 1821 Napoleon dies in exile on St. Helena on May, 5.
- 1821 Missouri admitted as 24th state on Aug 10.
- 1821 Thomas Jefferson writes autobiography. Describes many historical events.
- 1823 Monroe Doctrine given to Congress December 2.
- 1824 House of Representatives elects John Q. Adams president.
- 1825 John Quincy Adams takes oath on March 4 as 6th President.
- 1825 Erie Canal completed.
- 1826 July 4: John Adams dies in Quincy, MA, with last words, "Jefferson survives" not knowing that Jefferson had died a few hours earlier at Monticello, VA.
- 1827 Daniel Webster, takes seat in U.S. Senate... and changed it forever.
- 1827 Ludwig van Beethoven dies.
- 1827 Ohio Canal opened for business.
- 1828 Noah Webster publishes American Dictionary of English Language, Apr 14.
- 1828 Baltimore & Ohio railroad, the first designed for passengers & freight.
- 1829 Andrew Jackson takes oath on March 4 as 7th President.
- 1829 Estate of James Smithson leaves gift to U.S. Funds the Smithsonian.
- 1830 Abolition of slavery gains strong momentum in Northern States.