322 BC – Battle of Crannon between Athens and Macedonia.
461 – Roman Emperor Majorian is beheaded near the river Iria in north-west Italy following his arrest and deposition by the magister militum Ricimer.
626 – The Avar and Slav armies leave the siege of Constantinople.
936 – Coronation of King Otto I of Germany.
1420 – Construction of the dome of Santa Maria del Fiore begins in Florence.
1427 – The Visconti of Milan’s fleet is destroyed by the Venetians on the Po River.
1461 – The Ming dynasty Chinese military general Cao Qin stages a coup against the Tianshun Emperor.
1679 – The brigantine Le Griffon, commissioned by René-Robert Cavelier, Sieur de La Salle, is towed to the south-eastern end of the Niagara River, to become the first ship to sail the upper Great Lakes of North America.
1714 – The Battle of Gangut: The first important victory of the Russian Navy.
1782 – George Washington orders the creation of the Badge of Military Merit to honor soldiers wounded in battle. It is later renamed to the more poetic Purple Heart.
1789 – The United States Department of War is established.
1791 – American troops destroy the Miami town of Kenapacomaqua near the site of present-day Logansport, Indiana in the Northwest Indian War.
1794 – U.S. President George Washington invokes the Militia Acts of 1792 to suppress the Whiskey Rebellion in western Pennsylvania.
1819 – Simón Bolívar triumphs over Spain in the Battle of Boyacá.
1927 – The Peace Bridge opens between Fort Erie, Ontario and Buffalo, New York.
1930 – The last confirmed lynching of blacks in the Northern United States occurs in Marion, Indiana. Two men, Thomas Shipp and Abram Smith, are killed.
1933 – The Simele massacre: The Iraqi government slaughters over 3,000 Assyrians in the village of Simele. The day becomes known as Assyrian Martyrs Day.
1938 – The Holocaust: The building of Mauthausen concentration camp begins.
1940 – World War II: Alsace-Lorraine is annexed by the Third Reich.
1942 – World War II: The Battle of Guadalcanal begins as the United States Marines initiate the first American offensive of the war with landings on Guadalcanal and Tulagi in the Solomon Islands.
1946 – The government of the Soviet Union presented a note to its Turkish counterparts which refuted the latter’s sovereignty over the Turkish Straits, thus beginning the Turkish Straits crisis.
1964 – Vietnam War: The U.S. Congress passes the Gulf of Tonkin Resolution giving U.S. President Lyndon B. Johnson broad war powers to deal with North Vietnamese attacks on American forces.
1966 – Race riots occur in Lansing, Michigan.
1976 – Viking program: Viking 2 enters orbit around Mars.
1978 – U.S. President Jimmy Carter declares a federal emergency at Love Canal due to toxic waste that had been disposed of negligently.
1979 – Several tornadoes strike the city of Woodstock, Ontario, Canada and the surrounding communities.