The first day of the Seven Days' campaign begins with fighting at Oak Grove, Virginia.
Union troops surrounding Petersburg, Virginia, begin building a mine tunnel underneath the Confederate lines.
The U.S. Congress enacts legislation granting an eight-hour day to workers employed by the federal government.
Marie Curie announces her discovery of radium.
Ho Chi Minh travels to France for talks on Vietnamese independence.
The Soviet Union tightens its blockade of Berlin by intercepting river barges heading for the city.
North Korea invades South Korea, beginning the Korean War.
President Lyndon Johnson orders 200 naval personnel to Mississippi to assist in finding three missing civil rights workers.