June 21

• June 21, 217 BC
  Roman army is ambushed and destroyed by Hannibal's army, numbering around 55,000 troops, at the Battle of Lake Trasimene, which becomes the largest ambush in military history
• June 21, 1377
  Edward III, King of England, dies
• June 21, 1547
  The great fire in Moscow destroys sections of Moscow which had been built almost entirely of wood including some building in the Kremlin
• June 21, 1607
  The Church of England Episcopal Church, the first Protestant Episcopal parish in America, is established at Jamestown
• June 21, 1661
  Sweden signs the Treaty of Cardis, in which Russia agrees to return to Sweden areas it had conquered in the Baltic lands
• June 21, 1675
  Sir Christopher Wren begins to rebuild St Paul's Cathedral in London, replacing the old building which has been destroyed by the Great fire
• June 21, 1749
  English transport ships land 2576 colonists on what is now Nova Scotia to establish a British military base, naming the town Halifax
• June 21, 1788
  New Hampshire ratifies the United States Constitution as the ninth state, and by the terms of Article VII it is in effect
• June 21, 1834
  Obed Hussey, an American inventor, patents mechanical reaping machine
• June 21, 1887
  Britain celebrates the golden jubilee of Queen Victoria
• June 21, 1893
  George Washington Gale Ferris, engineer, completes the construction of a 77-meter high revolving steel wheel with 38 passenger cars, each with 40 plush chairs, for the World's Columbian Exposition in Chicago, the first Ferris wheel
• June 21, 1897
  In Austria a giant Ferris wheel, designed by Walter Bassett of England, is opened in Vienna to commemorate the 50th anniversary of the accession of Emperor Franz Joseph to the Habsburg throne
• June 22, 1940
  After German blitz France formally surrenders at the signing ceremony, held in the same wagon-lit railroad car used by French Marshal Ferdinand Foch to accept the surrender of Germany in 1918
• June 21, 1948
  In a lab in Manchester, England, the Small Scale Experimental Machine computer, nicknamed "Baby" is created, the first to contain memory (128 bytes) which could store a program
• June 21, 1985
  It is confirmed by American, German, and Brazilian forensic pathologists that the body exhumed in Brazil on June 6 is, indeed, that of the German physician in Auschwitz concentration camp, Josef Mengele