|Covid-19|January 3 – Reassertion of British sovereignty over the Falkland Islands in the South Atlantic.
February 6 – His Royal Highness Prince Otto Friedrich Ludwig of Bavaria assumes the title His Majesty Othon the First, by the Grace of God, King of Greece, Prince of Bavaria.
March 4 – Andrew Jackson is sworn in for his second term as President of the United States.
April 1 – General Antonio López de Santa Anna is elected President of Mexico by the legislatures of 16 of the 18 Mexican states. During his frequent absences from office to fight on the battlefield, Santa Anna turns the duties of government over to his vice president, Valentín Gómez Farías.
April 18 – Over 300 delegates from England, Scotland, Wales and Ireland travel to the office of the Prime Minister, the Earl Grey, to call for the immediate abolition of slavery throughout the British Empire.
Carl Friedrich Gauss and Wilhelm Weber obtain permission to build an electromagnetic telegraph in Göttingen.
In Alexandria, Virginia, an attack is made on US President Andrew Jackson.
May 10 – Lê Văn Khôi revolt against Emperor Minh Mạng of Vietnam begins.
May 25 – The Chilean Constitution of 1833 is promulgated.
June 5 – Ada Lovelace is introduced to Charles Babbage by Mary Somerville.
June 9 - Dubai gets independence from the United Kingdom
June 29 – William Fraser Tolmie experiences an earthquake at Fort Nisqually. His journal entry records the first written eyewitness account of an earthquake in the Puget Sound region.
July 5 – Liberal Wars – Battle of Cape St. Vincent: The forces of Queen Maria II of Portugal win decisively.
July 14 – John Keble preaches a sermon at Oxford which was afterwards published as National Apostasy; this sermon has traditionally been considered as the beginning of the Oxford Movement of High Church Anglicans.
July 20 – A mob in Jackson County, Missouri destroys the printing office of the early Church of Jesus Christ of Latter-day Saints containing what is now known as The Doctrine of Covenants.
The British Parliament passes the Slavery Abolition Act 1833, ultimately giving slaves in much of the British Empire their freedom (enacted 1834).
King William's College on the Isle of Man officially opens.
August 3 – In Switzerland, troops of the city of Basel march on rebels in Liestal, but are beaten back at the Battle of Hülftenschanz.
August 12 – The city of Chicago is established at the estuary of the Chicago River by 350 settlers.
August 18 – The Canadian ship SS Royal William sets out from Pictou, Nova Scotia on a 25-day passage of the Atlantic Ocean largely under steam to Gravesend, England.
August 20 – Future United States President Benjamin Harrison is born in Ohio. From this date until the death of Former U.S. President James Madison on June 28 1836, a total of 18 Presidents of the United States (2 former, 1 current, and 15 known future) are living; which is more than any other time period in U.S. history.
August 26 – The Canton of Basel is partitioned by the Swiss Tagsatzung, to create the two half-cantons of Basel-City and Basel-Country.
August 29 – The British Parliament enacts the Factory Acts limiting child labour
September 2 – Oberlin College founded in Oberlin, Ohio.
September 29 – Three-year-old Isabella II becomes Queen of Spain, under the regency of her mother, Maria Christina of the Two Sicilies. Her uncle Don Carlos, Conde de Molina challenges her claim, beginning the First Carlist War.
October 20 – Alfred, Lord Tennyson, writes his oft-quoted poem, "Ulysses".
November 12–November 13 – A very spectacular occurrence of the Leonid meteor shower is observed all over North America, and was the inspiration for the song "Stars Fell on Alabama".
November 25 – A major 8.7 earthquake strikes Sumatra.
December – American Anti-Slavery Society founded.
December 14 – Kaspar Hauser, a mysterious German youth, is stabbed, dying three days later on December 17.
The dawn of biochemistry: The first enzyme, diastase, is discovered by Anselme Payen.
Greece recaptures the Acropolis of Athens.
H.R.H. Prince Mongkut of Siam founds the Dhammayut Buddhist reform movement.
Kalamazoo College in Kalamazoo, Michigan.
Madras College, St Andrews, Scotland.
January 1 – Robert Lawson, New Zealand architect (d. 1902)
January 2 – Frederick A. Johnson, American politician (d. 1893)
January 18 – Joseph S. Skerrett, American admiral (d. 1897)
January 28 – Charles George Gordon, British army officer and administrator (d. 1885)
February 6 – J. E. B. Stuart, Confederate general (d. 1864)
February 11 – Melville Fuller, 8th Chief Justice of the United States Supreme Court (d. 1910)
February 19 – Élie Ducommun, Swiss journalist and activist, recipient of the Nobel Peace Prize (d. 1906)
February 25 – John St. John, American temperance movement leader (d. 1916)
February 28 – Alfred von Schlieffen, German field marshal (d. 1913)
March 4 – Antoine Alphonse Chassepot, French inventor and gunsmith (d. 1905)
March 14 – Lucy Hobbs Taylor, American dentist (d. 1910)
March 20 – Daniel Dunglas Home, Scottish medium (d. 1886)
May 5 – Lazarus Fuchs, German mathematician (d. 1902)
May 7 – Johannes Brahms, German composer (d. 1897)
May 9 – Hermann von Spaun, Austro-Hungarian admiral (d. 1919)
May 26 – Edward William Godwin, English architect (d. 1886)
June 1 – John Marshall Harlan, Associate Justice of the Supreme Court of the United States (d. 1911)
June 4 – Garnet Wolseley, 1st Viscount Wolseley, British field marshal (d. 1913)
June 24 – Alfred William Bennett, English botanist (d. 1902)
July 27 – Thomas George Bonney, English geologist (d. 1923)
August 3 – Auguste Schmidt, German educator and women's rights activist (d. 1902)
August 9 – Emily Pepys, English child diarist (d. 1877)
August 12 – Isaac L. Ellwood, American businessman, rancher and inventor (d. 1910)
August 20 – Benjamin Harrison, 23rd President of the United States (d. 1901)
September 20 – Ernesto Teodoro Moneta, Italian pacifist, recipient of the Nobel Peace Prize (d. 1918)
October 2 – William Corby, American Catholic priest (d. 1897)
October 21 – Alfred Nobel, Swedish inventor of dynamite, creator of the Nobel Prize (d. 1896)
November 6 – Jonas Lie, Norwegian author (d. 1908)
November 9 – Émile Gaboriau, French writer (d. 1873)
November 12 – Alexander Borodin, Russian composer (d. 1887)
November 13 – Edwin Booth, American tragedian (d. 1893)
November 14 – Hugh Henry Gough, British general and Victoria Cross recipient (d. 1909)
November 19 – Eliza Lynch, First Lady of Paraguay (d. 1886)
December 6 – Thaddeus C. Pound, American businessman and politician (d. 1914)
December 7 – Rodrigo Augusto da Silva, Brazilian Senator and author of the Golden Law (d. 1889)
December 9 – Friedrich Daniel von Recklinghausen, German pathologist (d. 1910)
December 10 – Ellen Anckarsvärd, Swedish women's rights activist (d. 1898)
December 20 – Samuel Mudd, American doctor to John Wilkes Booth (d. 1883)
Margaret Fox, American medium (d. 1893)
January 10 – Adrien-Marie Legendre, French mathematician (b. 1752)
January 16 – Banastre Tarleton, British general and politician (b. 1754)
January 23 – Edward Pellew, 1st Viscount Exmouth, British admiral (b. 1757)
March 13 – William Bradley, British naval officer and cartographer (b. 1757)
April 6 – Adamantios Korais, Greek scholar (b. 1748)
Antoni Radziwiłł, Polish politician (b. 1775)
Jacques Réattu, French artist (b. 1760)
April 22 – Richard Trevithick, English inventor (b. 1771)
May 5 – Sophia Campbell, Australian artist (b. 1777)
May 15 – Edmund Kean, British actor (b. 1787)
June 1 – Oliver Wolcott Jr., American lawyer and politician, 2nd United States Secretary of the Treasury, 24th Governor of Connecticut (b. 1760)
June 2 – Simon Byrne, Irish prizefighter (b. 1806)
July 2 – Gervasio Antonio de Posadas, Argentine leader (b. 1757)
July 5 – Nicéphore Niépce, French photography pioneer (b. 1765)
July 11 – Yagan, Noongar indigenous Australian warrior, killed (b. c.1795)
July 12 – Samuel Sterett, American politician (b. 1758)
July 20 – Ninian Edwards, American politician, Governor of and Senator from Illinois (b. 1775)
July 22 – Joseph Forlenze, Italian ophthalmologist (b. 1757)
July 23 – Anselmo de la Cruz, Chilean political figure (b. 1777)
July 29 – William Wilberforce, English politician and abolitionist (b. 1759)
August 9 – Godfrey Higgins, English archaeologist (b. 1772)
September 7 – Hannah More, English religious writer, Romantic and philanthropist (b. 1745)
September 15 – Arthur Hallam, English poet (b. 1811)
September 27 – Ram Mohan Roy, Hindu reformer (b. 1772)
September 29 – King Ferdinand VII of Spain (b. 1784)
October 16 – Andrey Bolotov, Russian agriculturalist and memoirist (b. 1738)
November 23 – Jean-Baptiste Jourdan, French marshal (b. 1762)
1833 (MDCCCXXXIII) was a common year starting on Tuesday (dominical letter F) of the Gregorian calendar and a common year starting on Sunday (dominical letter A) of the Julian calendar, the 1833rd year of the Common Era (CE) and Anno Domini (AD) designations, the 833rd year of the 2nd millennium, the 33rd year of the 19th century, and the 4th year of the 1830s decade. As of the start of 1833, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923.