British forces launch the Third Battle of Ypres in Flanders, beginning a four-month offensive through apocalyptic mud that costs over 475,000 casualties on both sides and becomes one of the defining symbols of World War I's futility.
A hurricane off the coast of Florida destroys eleven ships of the Spanish treasure fleet, killing over 1,000 sailors and scattering millions in gold and silver. The disaster crippled Spanish colonial finances and reshaped Caribbean naval power.
The 19-year-old Marquis de Lafayette receives his Continental Army commission as a major general, beginning one of the most important foreign contributions to the American Revolution.
British forces launch the Third Battle of Ypres in Flanders, beginning a four-month offensive through apocalyptic mud that costs over 475,000 casualties on both sides and becomes one of the defining symbols of World War I's futility.
French aviator and author of "The Little Prince" vanishes over the Mediterranean while flying a P-38 Lightning reconnaissance mission for the Free French Air Force. His disappearance remains one of aviation's enduring mysteries.
Italian mountaineers Achille Compagnoni and Lino Lacedelli reached the summit of K2, the world's second-highest peak and most technically demanding eight-thousander. The expedition's high-altitude oxygen, equipment, and physiology data shaped U.S. Army and Soviet mountain-warfare doctrine for decades.
NASA's Ranger 7 spacecraft returns the first close-up photographs of the lunar surface before impact, providing critical data for the Apollo program and demonstrating Cold War technological superiority.
NASA's Ranger 7 spacecraft impacted the Moon in Mare Cognitum after transmitting 4,316 close-up photographs, the first high-resolution images of the lunar surface returned by an American spacecraft. The successful mission vindicated the Ranger program after six previous failures and supported Apollo landing-site selection.
The U.S. Army's Chaparral short-range surface-to-air missile system reached full operational capability with the 5th Battalion, 59th Air Defense Artillery Regiment at Fort Bliss. The system, using a modified AIM-9D Sidewinder air-to-air missile on a tracked launcher, provided mobile point-air-defense for divisional operations through the 1990s.
The Professional Air Traffic Controllers Organization (PATCO) began a nationwide strike against the Federal Aviation Administration. President Reagan's decision to fire 11,345 striking controllers on August 5 reshaped U.S. civil aviation capacity, forced rapid FAA reliance on military air traffic controllers, and shifted labor-management relations across the federal government.
Presidents George H.W. Bush and Mikhail Gorbachev sign the Strategic Arms Reduction Treaty (START I), the first treaty requiring actual reduction of nuclear arsenals, calling for elimination of approximately 9,000 warheads.
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10 military events occurred on July 31, spanning multiple centuries. Key events include: Third Battle of Ypres (Passchendaele) Begins (1917), Lafayette Commissioned as Major General (1777), START I Treaty Signed (1991).
The most significant military event on July 31 is Third Battle of Ypres (Passchendaele) Begins (1917). British forces launch the Third Battle of Ypres in Flanders, beginning a four-month offensive through apocalyptic mud that costs over 475,000 casualties on both sides and becomes one of the defining symbols of World War I's futility.
Notable military figures born on July 31 include George Henry Thomas (1816–1870).
Events on July 31 span World War I, the Colonial & Revolutionary era, the Cold War, World War II, covering 10 events across 2 centuries of military history.
Events on July 31 involve 6 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.
