February 24
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Featured Event
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Pope Gregory XIII introduces a new calendar
On this day in 1582, Pope Gregory XIII issued a papal bull that would erase ten days of the year—Thursday, October 4, would be followed by Friday, October 15. This change overrode the Julian calendar, which had been the standard since 46 bce. Pope Gregory’s change accounted for the fact that a solar year is slightly shorter than 365.25 days (the year length used by the Julian calendar) and created a new system to address leap years. Roman Catholic countries began using the new calendar immediately, while others were more reluctant. Today, just four countries have not adopted the Gregorian calendar. [Read today’s edition of Today in History > >]
Featured Biography
Featured Biography
© Steve Granitz/WireImage
Born this day in 1971, American author Gillian Flynn is known for her darkly entertaining stories of murder and deceit in the Midwest.
Famous Birthdays
More on February 24
The Presidential Office of Ukraine (CC BY-SA 4.0)
2022
Russia launched a full-scale invasion of Ukraine. During the conflict’s first weeks, Ukrainian forces defeated a major Russian offensive, and Ukrainian civilians came under indiscriminate attack by the Russian military, causing millions of them to flee the country. [How many soldiers have died as a result of Russia’s invasion?]
NASA
2020
American mathematician Katherine Johnson died at age 101. Her trailblazing work as a computer (someone who manually performed calculations) for NASA helped send an astronaut into orbit for the first time and helped to orchestrate the first successful Moon landing. [Learn about more trailblazing computers in history.]
© cinemafestival/Shutterstock.com
2020
American film producer Harvey Weinstein, whose career ended amid numerous allegations of sexual harassment and assault, was convicted of rape and a criminal sex act; many viewed the verdict as a victory for the Me Too movement. Though his conviction was overturned in 2024, he was once again convicted of a felony sex crime the following year. [Learn about the activist behind the Me Too movement]
U.S. Department of Defense/National Archives, Washington, D.C.
1991
U.S. ground operations began in the Persian Gulf War, more than a month after the U.S. launched an air war against Iraq in response to Saddam Hussein’s invasion of Kuwait. [Read about the conflict’s key events in our timeline.]
Elliott Erwitt/Magnum Photos
1976
The regime of Fidel Castro adopted the constitution of Cuba, which mandated the operation of only one political party—the Communist Party of Cuba. [Discover six interesting facts about Castro]
Justin Sullivan/Getty Images
1955
Businessman Steve Jobs, cofounder of Apple Inc. and a charismatic pioneer of the personal computer era, was born. [Take our quiz about tech companies.]
Courtesy of the United States Information Agency
1942
The Voice of America made its first broadcast, in German, to counter the propaganda of Nazi leaders. [How much do you know about World War II?]
Library of Congress, Washington, D.C.
1868
The U.S. House of Representatives voted 126–47 to impeach President Andrew Johnson, whose Reconstruction policies regarding the South after the Civil War angered Radical Republicans. The move led to his political downfall, though he was acquitted by the Senate. [Do you know which U.S. presidents have been impeached?]
Library of Congress, Washington, D.C. (LC-DIG-pga-08724)
1848
The anti-monarchical Revolutions of 1848 reached France, the one nation where the insurgency was somewhat successful—and which led to the abdication of King Louis-Philippe. [Test your knowledge of French history.]
In a private collection
1836
Painter Winslow Homer, who captured the interaction of humans and nature in his watercolors, was born in Boston. [Take our quiz about artists.]
© G. Dagli Orti—DeAgostini/Getty Images
1821
Agustín de Iturbide put forth the Iguala Plan, in which he called for an independent Mexico ruled by a European prince (or himself, if such a prince could not be found). His plan also advocated for the Roman Catholic Church and military to retain their powers and equal rights for creoles and peninsulares. [Sort fact from fiction in our Latin America quiz.]
© Orhan Çam/stock.adobe.com
1803
In Marbury v. Madison, the U.S. Supreme Court declared an act of Congress unconstitutional, thus establishing the doctrine of judicial review. [Discover other notable decisions by the U.S. Supreme Court.]
Courtesy British Library, from the British Library archive (Foster 44)
1739
The Battle of Karnal pitted the invading forces of Nādir Shah of Iran against Muḥammad Shah, Mughal emperor of India. [Take our quiz about famous battles.]
Photos.com/Jupiterimages
1525
The forces of the Habsburg emperor Charles V annihilated the army of Francis I of France at the Battle of Pavia. [Test your knowledge of the history of war.]