| January 1 | 1st edition of New Rotterdam's Daily (3x per week) |
| January 15 | University of Notre Dame receives its charter in Indiana |
| January 25 | Recontre between Reps Weller and Shriver, U.S. House of Representative |
| February 3 | Hector Berlioz' "Carnaval Romain," premieres in Paris |
| February 27 | Dominican Republic gains independence from Haiti (National Day) |
| February 28 | 12-inch gun aboard USS Princeton explodes |
| March 9 | Giuseppe Verdi's opera "Hernani," premieres in Venice |
| March 21 | Origin of Baha'i Era-Baha'i calendar starts here (Baha 1, 1) |
| March 28 | Jose Zorilla's "Don Juan Tenorio," premieres in Madrid |
| April 12 | Texas became a U.S. territory |
| May 1 | Samuel Morse sends 1st telegraphic message |
| May 1 | Whig convention nominates Henry Clay as presidential candidate |
| May 6 | Johan Thorbecke argue general right to vote |
| May 23 | Declaration of Bab (Baha'i festival) ('Azamat 7, 1) |
| May 24 | Samuel FB Morse taps out "What hath God wrought" (1st telegraph msg) |
| May 25 | 1st telegraphed news dispatch is published in Baltimore Patriot |
| May 27 | Samuel F.B. Morse completes 1st telegraph line |
| June 6 | Young Men's Christian Association, YMCA, forms in London |
| June 15 | Goodyear patents vulcanization of rubber |
| June 26 | U.S. President John Tyler marries Julia Gardiner in New York City |
| July 27 | Fire destroys U.S. mint at Charlotte, North Carolina |
| July 29 | New York Yacht Club forms |
| July 30 | 1st U.S. yacht club organized, New York Yacht Club |
| August 8 | Brigham Young chosen Mormon Church head following Joseph Smith death |
| August 29 | 1st white-indian lacrosse game in Montreal, Indians win |
| September 5 | Iron ore discovered in Minnesota's Mesabi Mountains |
| September 25 | Canada defeat USA by 23 runs in the 1st cricket international |
| November 6 | Spain grants Dominican Rep independence |
| December 3 | RC Society Apostole of Prayer forms |
| December 4 | James K Polk elected 11th president of US |
| December 11 | 1st dental use of nitrous oxide, Hartford, Ct |
| December 30 | Opera "Stradella" after being rewritten is produced (Hamburg) |
