It is the 319th day of the year, with only 45 days remaining.
1821 - Missuori trader William Becknell arrives in Santa Fe, New Mexico over a route that became known as the Sante Fe Trail.
1863 - During the Battle of Campbell's Station near Knoxville, Tennessee, Confederate troops unsuccessfully attack Union forces.
1907 - Indian Territory and Oklahoma Territory are joined together to become the 46th U.S. state, Oklahoma.
1938 - LSD is first synthesized by Swiss chemist Dr. Albert Hofmann at the Sandoz Laboratories in Basel, Switzerland.
1940 - In occupied Poland, the Nazis close off the Warsaw Ghetto from the outside world.
1943 - American bombers strike a hydro-electric power facility and heavy water factory in German-controlled Vemork, Norway.
1945 - In operation Papercilip, the United States Army secretly admits 88 German scientists and engineers to help in the development of rocket technology.
1973 - President Richard Nixon signs the Trans-Alaska Pipeline Authorization Act into law, authorizing the construction of the Alaska Pipeline.
2000 - Bill Clinton becomes the first U.S. President to visit Vietnam since the end of the Vietnam War.