March 31

• March 31, 1084
  Anti-pope Clemens crowns German emperor Henry IV
• March 31, 1492
  King Ferdinand and Queen Isabella of Spain issue an edict expelling approximately 100,000 Jews from Spanish soil, except those willing to convert to Christianity
• March 31, 1683
  Emperor Leopold I and king of Poland, John Sobieski, signs covenant against Turkey
• March 31, 1774
  English Parliament passes the Boston Port Act, the first bill of the Intolerable Acts, which closes Boston harbor until restitution for the destroyed tea is made
• March 31, 1790
  In Paris, France, Maximilien de Robespierre is elected president of the Jacobin Club, the most influential political club in the development of the French Revolution
• March 31, 1814
  Alexander I of Russia enters Paris at the head of an anti-Napoleon coalition
• March 31, 1840
  American President Martin Van Buren issues an executive order extending the "10-hour system" to all laborers and mechanics employed on federal public works, as the average daily hours of factory workers was estimated at 11.4
• March 31, 1854
  The Treaty of Kanagawa, concluded between Commodore Matthew C. Perry of the United States Navy and the Tokugawa shogunate, forces Japan to opens ports to foreign trade and formally ends Japan's policy of isolation
• March 31, 1880
  Wabash, Indiana, United States becomes the first town in the world completely illuminated by electrical lighting
• March 31, 1885
  Britain establishes a protectorate over Bechuanaland, modern Botswana, after appeals by the Botswana leaders for assistance
• March 31, 1889
  French engineer Gustave Eiffel unfurls the French tricolor from atop the Eiffel Tower, constructed of 7,000 tons of iron and steel, officially marking its completion
• March 31, 1896
  Whitcomb Judson, of Chicago, Illinois, United States, patents a hookless fastening, i.e. zipper
• March 31, 1903
  Richard Pearse, a New Zealand farmer and inventor, flies monoplane several hundred meters in New Zealand, some nine months before the Wright brothers flew their aircraft
• March 31, 1907
  Romanian Army puts down Moldavian farmers' revolt, begun due to the inequity of land ownership, killing roughly 11,000
• March 31, 1931
  An earthquake destroys Managua, Nicaragua, killing 2,000 people
• March 31, 1999
  The Matrix, a science fiction action film depicting a dystopian future, is released
• March 31, 2007
  Sydney, Australia, turns off its lights for one hour between 7:30PM and 8:30PM as a political statement for Global Climate Change for the first time