- Jan 3 Danish national anthem "Kong Kristian stod ved højen mast" 1st sung
- Jan 4 Snowstorm hits George Washington's army at Morristown, New Jersey
- Jan 15 American Continental Congress establishes court of appeals
Herschel Discovers a Binary Star
May 2 William Herschel discovers 1st binary star, Xi Ursae Majoris
American Academy of Arts and Sciences
May 4 American Academy of Arts & Science founded in Boston, James Bowdoin, John and Samuel Adams founding members
- May 4 Charles Bunbury on Diomed wins 1st Epsom Derby
Siege of Charleston Ends
May 12 American General Benjamin Lincoln surrenders Charleston to the British (Revolutionary War)
- May 19 About midday, near-total darkness descends on New England, now known to be caused by forest fires in Canada
- May 29 Battle of Waxhaw Creek: alleged massacre of 113 of Colonel Abraham Buford's continentals by Lieutenant Colonel Banastre Tarleton's troops after the continentals raised a white flag
- Jun 2 Anti-Catholic demonstration attacks parliament in London
- Jun 7 Anti-Catholic riot in London, hundreds die
- Jun 23 American Revolution: Battle of Springfield fought in and around Springfield, New Jersey (including Short Hills, formerly of Springfield, now of Millburn Township
- Jul 9 Denmark declares neutrality, joining First League of Armed Neutrality to protect shipping
Event of Interest
Jul 10 The comte de Rochambeau and his French force of 7,000 land at Newport, Rhode Island, to join the American Revolutionary War
Selling West Point
Sep 21 Benedict Arnold gives British Major John André plans to West Point
- Sep 23 British Major John Andre reveals Benedict Arnold's plot to betray West Point
- Sep 25 American army officer Benedict Arnold defects to the British
- Oct 7 British defeated by American militia near Kings Mountain, SC
- Oct 10 Great Hurricane of 1780 kills 20,000 to 30,000 in the Caribbean, hitting Barbados first. Atlantic's deadliest recorded hurricane.
- Oct 16 Royalton, Vermont and Tunbridge, Vermont last major raid of the American Revolutionary War
Hancock Elected Governor
Oct 25 John Hancock elected the first Governor of Massachusetts in a landslide with over 90% of the vote
Admirals
Aviators
Gangsters
Generals
Industrialists
Suffragists