Warsaw Pact forces led by the Soviet Union invaded Czechoslovakia with 200,000 troops and 2,000 tanks to crush the Prague Spring reform movement. The invasion ended Alexander Dubček's attempt to create "socialism with a human face" and demonstrated that the Soviet Union would use military force to maintain control over its satellite states.
Tchaikovsky's "1812 Overture," commemorating Russia's defense against Napoleon's invasion, premiered in Moscow. The piece, famously scored for cannon fire and church bells, became one of the most recognizable works of military-themed classical music and a staple of American Independence Day celebrations.
Winston Churchill delivered his famous tribute to the RAF pilots fighting the Battle of Britain: "Never in the field of human conflict was so much owed by so many to so few." The speech, delivered to the House of Commons, became one of the most quoted military orations in the English language.
Leon Trotsky, former commander of the Red Army and exiled rival of Stalin, was attacked with an ice axe at his home in Coyoacan, Mexico by NKVD agent Ramon Mercader. Trotsky died the following day, eliminating Stalin's most dangerous ideological rival and ending the last major institutional alternative to Stalinist control of Soviet military and political doctrine.
Prime Minister Winston Churchill delivered his Never Was So Much Owed By So Many To So Few speech in the House of Commons on August 20, 1940, honoring the RAF Fighter Command pilots fighting the Battle of Britain and framing the strategic bombing campaign that would shape the remainder of the war.
American and Polish forces closed the Falaise Gap, completing the encirclement of the German Seventh Army and Fifth Panzer Army in Normandy. Although 40,000 Germans escaped, the pocket's destruction eliminated two German field armies and opened the road to Paris and beyond.
Warsaw Pact forces led by the Soviet Union invaded Czechoslovakia with 200,000 troops and 2,000 tanks to crush the Prague Spring reform movement. The invasion ended Alexander Dubček's attempt to create "socialism with a human face" and demonstrated that the Soviet Union would use military force to maintain control over its satellite states.
NASA launched the Voyager 2 spacecraft from Cape Canaveral on a Titan IIIE-Centaur rocket to begin its Grand Tour of the outer solar system. The spacecraft's instruments and communications technology, developed in partnership with the U.S. Air Force and Deep Space Network, pioneered techniques still used for military reconnaissance and deep-space surveillance.
Voyager 2 lifted off from Cape Canaveral aboard a Titan III-Centaur rocket on August 20, 1977, beginning a grand tour mission that would deliver the first detailed reconnaissance of Jupiter, Saturn, Uranus, and Neptune while the spacecraft carried the only civilian payload ever protected by a military-grade radioisotope thermoelectric generator.
The Supreme Council of Estonia formally declared independence from the Soviet Union during the attempted coup against Mikhail Gorbachev. Iceland recognized Estonian independence within hours, and the declaration triggered a cascade of Baltic sovereignty that the collapsing Soviet military was unable to prevent.
The United States launched cruise missile strikes against al-Qaeda training camps in Afghanistan and a pharmaceutical factory in Sudan in retaliation for the embassy bombings in East Africa. The strikes, part of Operation Infinite Reach, failed to kill Osama bin Laden and the Sudan target was later revealed to have had no connection to weapons production.
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Brevet Brigadier General
U.S. President (1889-1893) who served as a brigade commander in the Civil War under Sherman during the Atlanta Campaign and the March to the Sea. As President, he oversaw significant naval expansion, including the commissioning of the first modern battleships.
Prime Minister of India (1984-1989) who sent the Indian Peace Keeping Force to Sri Lanka and oversaw India's military modernization program. He was assassinated by a Tamil Tigers suicide bomber in 1991, one of the first major political assassinations by a modern terrorist organization.
American patriot whose midnight ride on April 18, 1775, warning of the British advance toward Lexington and Concord, became the most famous act of military intelligence in American history. He also served as a lieutenant colonel of artillery in the Massachusetts militia.
10 military events occurred on August 20, spanning multiple centuries. Key events include: Soviet Invasion of Czechoslovakia (1968), Encirclement of the Falaise Pocket Complete (1944), Churchill's "The Few" Speech (1940).
The most significant military event on August 20 is Soviet Invasion of Czechoslovakia (1968). Warsaw Pact forces led by the Soviet Union invaded Czechoslovakia with 200,000 troops and 2,000 tanks to crush the Prague Spring reform movement. The invasion ended Alexander Dubček's attempt to create "socialism with a human face" and demonstrated that the Soviet Union would use military force to maintain control over its satellite states.
Notable military figures born on August 20 include Benjamin Harrison (1833–1901), Rajiv Gandhi (1944–1991).
Events on August 20 span the Cold War, World War II, the Interwar Period, the Modern Era, covering 10 events across 2 centuries of military history.
Events on August 20 involve 3 branches of the U.S. and allied armed forces, reflecting the global scope of military operations throughout history.
Explore military history from the day you were born.
June 6
The Allied invasion of Normandy, the largest amphibious assault in history.
December 7
Japan attacks the U.S. Pacific Fleet, bringing America into World War II.
September 11
The deadliest terrorist attack in history transforms U.S. national security.
August 6
The first atomic bomb is dropped on a city, ushering in the nuclear age.
May 8
Nazi Germany surrenders unconditionally, ending World War II in Europe.
November 11
Armistice Day marks the end of World War I and honors all who served.
June 4
The turning point of the Pacific War as the U.S. Navy destroys four Japanese carriers.
July 4
The Declaration of Independence is adopted, sparking the American Revolution.
The FIM-92 Stinger helped win the Cold War by turning Afghan mujahideen into a credible anti-aircraft threat. By 2023, the United States almost ran out of them, because Raytheon stopped making them for 13 years, and the first 10 months of Ukraine support burned through the remaining stockpile.
These weapons were built to fight a war that everyone prayed would never happen. The Minuteman III has been on alert since 1970. The Typhoon-class carried enough nuclear warheads to destroy a continent. The Davy Crockett could be fired by three soldiers. Most of them have been waiting for 40 years. Here are 10 Cold War weapons built exclusively for World War III.
The MiG-31 was designed to catch the SR-71 Blackbird. It is still the fastest fighter in any air force. The Foxhound's Zaslon phased-array radar, the first ever installed in a fighter, can track 10 targets and engage 4 simultaneously at ranges exceeding 200 miles. Here is why Russia still flies a 1980s interceptor, and why the MiG-31BM carrying a Kinzhal hypersonic missile has changed what the aircraft means to modern warfare.
Nineteen armies on four continents chose the Leopard 2. No other Western tank comes close to this export record, and the reasons go far beyond German engineering.
