Historical Events on August 21

29 significant historical events occurred on August 21. August 21 has seen various important historical events over the years, with five notable occurrences on this date. These events include wartime milestones and scientific developments. In 1942, the Battle of the Tenaru took place during World War II. In 1945, the demon core incident led to fatalities involving plutonium. In 1968, the Warsaw Pact invaded Czechoslovakia. In 2005, the Turkish Grand Prix Formula One race occurred. A total solar eclipse was widely observed across the United States in 2017.