Year 1791 (MDCCXCI) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 11-day slower Julian calendar).

Events of 1791

January - June

• January 25 - The British Parliament passes the Constitutional Act of 1791, splitting the old province of Quebec into Upper and Lower Canada.
• March 2 - Long-distance communication speeds up with the unveiling of a semaphore machine in Paris.
• March 4 - Vermont is admitted as the 14th U.S. state.
• May 3 - The Polish-Lithuanian Commonwealth Sejm (Parliament) proclaims the Constitution of third May, the first modern codified constitution in Europe.

July - December

• July 14 - The Priestley Riots in Birmingham, England.
• June 20 - The French Royal Family is captured when they try to flee in disguise.
• August 6 - Brandenburg Gate in Berlin finished.
• August 26 - John Fitch is granted a patent for the steamboat in the United States.
• September 25 - The Mission Santa Cruz, is founded by Father Fermín Francisco de Lasuén, becoming the twelfth mission in the California mission chain.
• September 30 - Première of Wolfgang Amadeus Mozart's singspiel Die Zauberflöte (Magic Flute) in the in Vienna.
• October 9 - The Mission Nuestra Señora de la Soledad, was founded by Father Fermín Francisco de Lasuén, becoming the thirteenth mission in the California mission chain.
• December 4 - The first issue of The Observer, the world's first Sunday newspaper, is published.
• December 5 - Austrian composer, Wolfgang Amadeus Mozart dies.
• December 15 - Ratification by the states of the first ten amendments to the United States Constitution is completed, creating the United States Bill of Rights. Two additional amendments remain pending, and one of these is finally ratified in 1992, becoming the Twenty-seventh Amendment.

• “1791” Pittsfield, MA 01201 - the year in which an ordinance was written barring the game of baseball within 80 yards of the Meeting House, the first known reference to the game of baseball in North America.

Undated

• The first American ship reaches Japan.
• Slave rebellion in Haiti has begun.

Ongoing events

• French Revolution (1789-1799).

Births

• January 15 - Franz Grillparzer, Austrian writer (d. 1872)
• January 28 - Louis Joseph Ferdinand Herold, French composer (d. 1833)
• February 12 - Peter Cooper, American Industrialist, inventor and philanthropist (d. 1883)
• February 21
  • Carl Czerny, Austrian composer (d. 1857)
  • John Mercer, chemist and industrialist (d. 1866)
• April 23 - James Buchanan, 15th President of the United States (d. 1868)
• April 27 - Samuel Morse, American inventor (d. 1872)
• July 26 - Franz Xaver Wolfgang Mozart, Austrian composer and pianist (d. 1844)
• September 5 - Giacomo Meyerbeer, German composer (d. 1864)
• September 21 - István Széchenyi, Hungarian politician and writer (d. 1860)
• September 22 - Michael Faraday, British scientist (d. 1867)
• September 26 - Théodore Géricault, French painter (d. 1824)
• November 11 - Josef Munzinger, member of the Swiss Federal Council (d. 1855)
• December 26 - Charles Babbage, British mathematician and inventor (d. 1871)

See also Category: 1791 births.

Deaths

• January 11 - William Williams Pantycelyn, Welsh hymnist (b. 1717)
• March 2 - John Wesley, English founder of Methodism (b. 1703)
• March 14 - Johann Salomo Semler, German historian and Bible commentator (b. 1725)
• April 19 - Richard Price, Welsh philosopher (b. 1723)
• May 9 - Francis Hopkinson, American signer of the Declaration of Independence (b. 1737)
• June 5 - Frederick Haldimand, Swiss-born British colonial governor (b. 1718)
• June 10 - Toussaint-Guillaume Picquet de la Motte, French admiral (b. 1720)
• July 17 - Martin Dobrizhoffer, Austrian Jesuit missionary (b. 1717)
• July 25 - Isaac Low, American delegate to the Continental Congress (b. 1735)
• August 16 - Charles-François de Broglie, marquis de Ruffec, French soldier and diplomat (b. 1719)
• November 4 - Richard Butler (general), American soldier (b. 1743)
• September 25 - William Bradford, American printer (b. 1719)
• December 5 - Wolfgang Amadeus Mozart, Austrian composer (b. 1756)

See also Category: 1791 deaths.