1821 - Costa Rica, Guatemala, Honduras, Nicaragua and El Salvador proclaimed independence.
1916 - During the Battle of the Somme, in France, tanks were first used in warfare when the British rolled them onto the battlefields.
1917 - Alexander Kerensky proclaimed Russia to be a republic.
1928 - Alexander Fleming discovered the antibiotic penicillin in the mold Penicillium notatum.
1935 - The Nuremberg Laws were enacted by Nazi Germany. The act stripped all German Jews of their civil rights and the swastika was made the official symbol of Nazi Germany.
1940 - The German Luftwaffe suffered the loss of 185 planes in the Battle of Britain. The change in tide forced Hitler to abandon his plans for invading Britain.
1961 - The U.S. resumed underground testing of nuclear weapons.
1971 - Greenpeace was founded.
1990 - France announced that it would send an additional 4,000 soldiers to the Persian Gulf. They also expelled Iraqi military attaches in Paris.
1998 - Ayatollah Ali Khamenei ordered the Iranian military to be on full alert and massed troops on its border with Afghanistan.