February 28 - The charter establishing the institution now known as the University of Pittsburgh is granted.
May 13 - Captain Arthur Phillip leaves Portsmouth, England with eleven ships full of convicts (First Fleet) to establish a penal colony in Australia.
May 25 - In Philadelphia, Pennsylvania, delegates convene a Constitutional Convention to write a new Constitution for the United States. George Washington presides.
June 20 - Oliver Ellsworth moves at the Federal Convention to call the government the United States.
July 13 - The Continental Congress enacts the Northwest Ordinance establishing governing rules for the Northwest Territory. It also establishes procedures for the admission of new states and limits the expansion of slavery.
August 6 - Sixty proof sheets of the Constitution of the United States are delivered to the Constitutional Convention.
September 17 - The United States Constitution is signed in Philadelphia, Pennsylvania.
September 28 - The newly completed United States Constitution is voted on by the U.S. Congress to be sent to the state legislatures for approval.
October 1 - Russians under Suvorov defeat the Turks at Kinburn.
October 29 - Mozart's opera Don Giovanni receives its first performance in Prague.
December 7 - Delaware becomes the first state to ratify the US Constitution.
December 12 - Pennsylvania becomes the second state to ratify the United States Constitution five days after Delaware became the first.
December 18 - New Jersey becomes the third state to ratify the U.S. Constitution.