September 23 - José Gervasio Artigas, Uruguayan hero (b. 1764)
Events
January 29 - Henry Clay introduces the Compromise of 1850 to the U.S. Congress.
February 28 - The University of Utah opens in Salt Lake City, Utah.
March 5 - The Britannia Bridge across the Menai Strait between the Isle of Anglesey and the mainland of Wales is opened.
March 7 - United States Senator Daniel Webster gives his "Seventh of March" speech in which he endorses the Compromise of 1850 in order to prevent a possible civil war.
March 18 - American Express is founded by Henry Wells and William Fargo.
April 4 - The Great Fire of Cottenham, a large part of the Cambridgeshire village (England) is burnt to the ground under suspicious circumstances.
April 4 - Los Angeles, California is incorporated as a city.
June 3 - The traditional founding date of Kansas City, Missouri. This was the date on which it was first incorporated by Jackson County, Missouri as the "City of Kansas".
July 2 - The self-contained gas mask is patented by Benjamin J. Lane.
July 9 - President Zachary Taylor dies and Millard Fillmore becomes the 13th President of the United States.
July 10 - Millard Fillmore is inaugurated as the 13th President of the United States upon the death of President Zachary Taylor, 16 months into his term.
September 9 - California is admitted as the thirty-first U.S. state.
September 9 - The Compromise of 1850 strips Texas of a third of its claimed territory (now parts of Colorado, Kansas, New Mexico, Oklahoma, and Wyoming) in return for the U.S. federal government assuming $10 million of Texas's pre-annexation debt.
September 18 - The U.S. Congress passes the Fugitive Slave Law of 1850.
September 29 - The Roman Catholic hierarchy is re-established in England and Wales by Pope Pius IX.
November 24 - Danish troops defeat a Schleswig-Holsteinian force in the Schleswig-Holsteinian town of Lottorf.
November 29 - The treaty, Punctation of Olmütz, signed in Olomouc means diplomatic capitulation of Prussia to Austrian Empire, which took over the leadership of German Confederation.
December 16 - History of New Zealand: The Charlotte-Jane and the Randolph bring the first of the Canterbury Pilgrims to Lyttelton.
