- 1917: The Communist Revolution in Russia led to the fall of the Tsarist dictatorship. The fall led to the beginning of the Soviet Union.
- 1939: The Manhattan Project was created in secrecy under the Roosevelt administration to develop the first atomic bomb.
- 1939-1945: World War II was a war involving 70 nations. The war began when Nazi Germany invaded Poland.
- 1941: Germany invaded the Soviet Union during World War II on June 22, 1941.
- 1945: World War II ended when the Soviet Union defeated Berlin.
- 1948: The splitting of Korea was the result of the Korean War. The Korean Demilitarized Zone (DMZ) was created on July 27,1953 as militarized border between North Korea ad South Korea. The DMZ currently still divides North Korea and South Korea.
- 1948: The defeat of Nazi Germany divided Germany into four occupied zones.
- 1949: The Chinese Civil War that began in 1927 led to communist control over China by the Pingjin campaign.
- 1949: The Soviet Union tested its first nuclear weapon on August 29, 1949.
- 1950: On June 25, 1950 North Korea invaded South Korea starting the Korean War.
- 1950: Communist control over Vietnam was one of the causes of the Vietnam War.
- 1953: On July 27,1953 the acceptance of the Korean War Armistice by the United Nations ended the Korean War.
- 1955: On May 15, 1995 Austria was re-established as a sovereign State as a result of the Austrian State Treaty.
- 1957: The Soviet union launched the first artificial satellite, Sputnik on October 4, 1957.
- 1959: On January 1, 1959 Fidel Castro forced Fulgecio Batisto from power and took control of Cuba.
- 1960: After a shooting down of an American fighter jet by the Soviet Union, President Eisenhower and Khrushchev have a summit conference in Paris. The negotiations fail.
- 1961: On April 17, 1961 Cuban exiles supported by the United States made a failed attempt to overthrow the Cuban government.
- 1962: On October 15, 1962 the United States was on heightened alert because of Soviet missile construction in Cuba.
- 1963: Lee Harvey Oswald assassinates President John F. Kennedy on November 22, 1963.
- 1965: In March 1965 the United States enters the Vietnam War.
- 1969: On July 16, 1969 the United States puts Neil Armstrong the first man on the moon.
- 1975: In April 1975 the North Vietnamese Army captured Saigon resulting in the end of the Vietnam War.
- 1969-1972: The first round of treaty negotiations between the United States and the Soviet Union.
- 1972:President Nixon visited China and succeeded in ending the isolation between the United Sates and the Republic of China.
- 1981: The inauguration of Ronald Reagan the 40th President.
- 1983: President Reagan creates the Strategic Defense Initiative on March 23, 1983.
- 1985: Gorbachev becomes general secretary of the Soviet Union.
- 1987: In a speech on June 12, 1987 President Reagan challenges Gorbachev to tear down the Berlin Wall.
- 1989: The fall of the Berlin Wall on November 9, 1989.
- 1991: The dissolution of the Soviet Union at the end of the Cold War.