1784 1785 1786 - 1787 - 1788 1789 1790
| Decades: |
1750s 1760s 1770s - 1780s - 1790s 1800s 1810s
Events of 1787
- January 6 – The North Carolina General Assembly authorizes nine commissioners to purchase 100 acres (0.40 km2) of land for the county seat of Chatham County. The town is named Pittsborough (later shortened to Pittsboro) for William Pitt the Younger.
- January 11 – William Herschel discovers Titania and Oberon, 2 moons of Uranus.
- February 4 – Shays' Rebellion fails.
- February 28 – A charter is granted establishing the institution known today as the University of Pittsburgh.
- April 2 – A Charter of Justice is signed providing the authority for the establishment of the first New South Wales (ie Australian) Courts of Criminal and Civil Jurisdiction.
- May 13 – Captain Arthur Phillip leaves Portsmouth, England with 11 ships packed with 1,000 convicts and their jailers to establish a penal colony in Australia.
- May 14 – In Philadelphia, Pennsylvania, delegates begin arriving to write a new Constitution for the United States.
- May 25 – In Philadelphia, Pennsylvania, delegates begin to convene a Constitutional Convention intended to amend the Articles of Confederation. However, a new Constitution for the United States is eventually produced. George Washington presides over the Convention.
- May – Orangist troops attack Vreeswijk, Harmelen and Maarssen; civil war starts in the Netherlands.
- June 6 – Franklin College, named for Benjamin Franklin, opens in Lancaster, Pennsylvania. It later merges with Marshall College to become Franklin and Marshall College.
- June 20 – Oliver Ellsworth moves at the Federal Convention that the government be called the United States.
- June 28 – Princess Wilhelmina of Orange, sister of Frederick, the king of Prussia, is captured by patriots and taken to Goejanverwellesluis, and not allowed to travel to the Hague.
- July 13 – The U.S. 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.
- July 15 – Lord's cricket ground is established and the MCC incorporated.
- August 27 – Launching a 45-foot (14 m) steam powered craft on the Delaware River, John Fitch demonstrates the first U.S. patent for his design.
- September 13 – Prussian troops enter the Netherlands. Within a few weeks 40,000 Patriots (out of a population of 2,000,000) go into exile in France (and learn from observation the ideals of the French Revolution).
- September 17 – The United States Constitution is adopted by the Constitutional Convention in Philadelphia.
- October 1 – Russo-Turkish War, 1787-1792 – Battle of Kinburn: Alexander Suvorov, though sustaining a wound, routs the Turks.
- October 27 – The first of the Federalist Papers, a series of essays calling for ratification of the U.S. Constitution, is published in a New York paper.
- October 29 – Wolfgang Amadeus Mozart's opera Don Giovanni (libretto by Lorenzo da Ponte) premieres in the Estates Theatre in Prague.
- December 7 – Delaware ratifies the Constitution and becomes the first U.S. state.
- December 8 – Mission La Purisima Concepcion is founded by Father Fermín Francisco de Lasuén, becoming the 11 mission in the California mission chain.
- December 12 – Pennsylvania becomes the second U.S. state.
- December 18 – New Jersey becomes the third U.S. state.