| January 3 | Scottish factory owner Robert Owen buys 30,000 acres in Indiana as site for New Harmony utopian community |
| January 19 | Ezra Daggett and nephew Thomas Kensett patent food storage in tin cans |
| January 25 | 1st U.S. engineering college opens, Rensselaer Polytechnic, Troy, New York |
| February 3 | Dutch North Sea coast floods |
| February 5 | Hannah Lord Montague of New York creates 1st detachable shirt collar |
| February 9 | House of Representatives elects John Quincy Adams 6th U.S. president |
| February 12 | Creek Indian treaty signed. Tribal chiefs agree to turn over all their land in Georgia to the government and migrate west by Sept 1, 1826 |
| February 19 | Franz Grillparzer's "Konig Ottokars Gluck," premieres in Vienna |
| February 22 | Russia and Britain establish Alaska-Canada boundary |
| March 2 | 1st grand opera in U.S. sung in English, New York City |
| March 4 | John Quincy Adams inaugrated as 6th president |
| April 10 | 1st hotel in Hawaii opens |
| April 10 | Nicaraguan constituent assembly meets at Leon |
| April 19 | 33 patriotic exiles return to Uruguay |
| May 20 | Charles X becomes King of France |
| May 21 | Prince Willem FK marries Louise AWA of Prussia |
| May 25 | American Unitarian Association founded |
| June 4 | Unseasonable hurricane hits New York City |
| June 13 | Walter Hunt patents safety pin |
| June 19 | Gioacchino Rossini's "Il viaggio a Reims," premieres |
| June 20 | Coronation of French king Charles X the Bourbon |
| July 21 | Java princess Dipo Negoro/Mangkubumi declare war on all non-islamics |
| August 6 | Bolivia gains independence from Peru (National Day) |
| August 14 | Dutch King Willem I throws foreign students out |
| August 25 | Uruguay declares independence from Brazil (National Day) |
| September 27 | Railroad transportation is born with 1st track (Stockton-Darlington) |
| October 17 | 1st French Liszts operette Don Sanche premieres in Paris |
| October 25 | Erie Canal opens, linking Great Lakes and Atlantic Ocean |
| October 26 | Erie Canal between Hudson River and Lake Erie opened |
| November 26 | 1st college fraternity founded (Kappa Alpha (Union College, New York)) |
| November 29 | 1st Italian opera in U.S., "Barber of Seville" premieres (New York City) |
| December 6 | President John Quincy Adams suggests establishment of a U.S. observatory |
| December 14 | Decembrist uprising in Russia against Tsar Nicholas I begins |
| December 26 | Erie Canal opens |
| December 27 | 1st public railroad using steam locomotive completed in England |
