On this day in 1933, the United States recognized Soviet Union.
On this day in 1969, U.S. and Soviet Union began negotiations aimed at limiting the strategic weapons on both sides during the Cold War.
On this day in 1970, Lieutenant William Calley went on trial for the My Lai Massacre in the Vietnam War.
On this day in 1989, during the Cold War, in Czechoslovakia, an uprising aimed at overthrowing the communist government, later on known as Velvet Revolution, began. (It succeeded on December 29).