356 BC – The Temple of Artemis in Ephesus, one of the Seven Wonders of the World, is destroyed by arson.
1861 – First Battle of Bull Run: At Manassas Junction, Virginia, the first major battle of the Civil War ends in a victory for the Confederate army.
1865 – In the town square of Springfield, Missouri, ‘Wild Bill’ Hickok and Davis Tutt engage in what is regarded as the first western showdown gun fight with Hickok killing Tutt with a single shot.
1873 – At Adair, Iowa, Jesse James and the James–Younger Gang pull off the first successful train robbery in the U.S.
1925 – In Dayton, Tennessee, high school biology teacher John T. Scopes is found guilty of teaching evolution in his school class and fined $100.
1944 – American troops land on Guam, starting a battle that will end on August 10. In Berlin, five conspirators are executed for the plot to assassinate Adolf Hitler.
1949 – The Senate ratifies the North Atlantic Treaty, creating NATO.
1954 – The Geneva Conference partitions Vietnam into North Vietnam and South Vietnam.
1961 – Mercury-Redstone 4 Mission astronaut Gus Grissom, piloting Liberty Bell 7 becomes the second American to go into space
1969 – At 02:56 UTC, at Tranquility Base, astronaut Neil Armstrong leaves the Lunar Lander Eagle and becomes the first person to walk on the Moon. At 17:54 UTC, the Eagle lifts off from the Moon to redock with the Command Module Columbia at 21:35 UTC
1979 – Jay Silverheels becomes the first Native American to have a star commemorated in the Hollywood Walk of Fame.
1983 – The world’s lowest temperature in an inhabited location is recorded at Vostok Station, Antarctica at −128.6 °F, (−89.2 °C)
2011 – NASA’s Space Shuttle program ends with the landing of Space Shuttle Atlantis on mission STS-135.