Today In History
April 20 in History
Your birthday shares the stage with stories that shaped the world. Born on this day: Adolf Hitler, Napoleon III, and Daniel Chester French.

Curie Isolates Radium: The Age of Radioactivity Begins
Marie and Pierre Curie isolated a new element from pitchblende that emitted carmine spectral lines never before documented, proving their sample contained something far more radioactive than uranium. They named this substance radium after its ability to emit energy as rays, a discovery that fundamentally expanded the understanding of atomic physics and launched the field of radioactivity research.
Famous Birthdays
1889–1945
d. 1873
Daniel Chester French
b. 1850
David Filo
b. 1966
Felix Baumgartner
1969–2025
Gro Harlem Brundtland
b. 1939
Harold Lloyd
d. 1971
K. Alex Müller
b. 1927
Killer Mike
b. 1975
Luther Vandross
1951–2005
Mike Portnoy
b. 1967
Rose of Lima
1586–1617
Historical Events
Marie and Pierre Curie isolated a new element from pitchblende that emitted carmine spectral lines never before documented, proving their sample contained something far more radioactive than uranium. They named this substance radium after its ability to emit energy as rays, a discovery that fundamentally expanded the understanding of atomic physics and launched the field of radioactivity research.
Over a thousand Cuban refugees arrived in Florida aboard makeshift vessels, triggering an immediate federal crisis that forced the U.S. government to establish emergency processing centers and eventually negotiate a new immigration framework. This sudden influx of 125,000 people reshaped American demographics in South Florida and strained Cold War diplomatic relations between Washington and Havana for years.
Colonial militia forces surrounded British-held Boston the day after the battles of Lexington and Concord, trapping General Gage's garrison inside the city. The eleven-month siege bottled up the most powerful army in the world until Henry Knox's artillery from Fort Ticonderoga forced a British evacuation by sea.
Radical France declared war on the Habsburg monarch, igniting a conflict that would engulf Europe for over two decades. The declaration transformed France's internal revolution into a continental crusade, unleashing armies driven by nationalist fervor against the monarchies determined to crush the republic before its ideas could spread.
A mother and son fought over Jerusalem, not for glory, but for who held the reins of power. For eight years, Baldwin III and Queen Melisende clashed, tearing their own kingdom apart with rival armies and shifting loyalties. The blood spilled was real; friends turned on friends in the dusty streets of Acre. Finally, in 1152, they made peace, splitting the throne without a single drop more shed. But here's the twist: that fragile unity lasted only a decade before Saladin swept them both away.
Admiral Robert Blake sailed his fleet into the harbor of Santa Cruz de Tenerife and destroyed an entire Spanish treasure fleet under the guns of shore batteries, one of the most audacious naval raids of the century. The victory severed Spain's silver lifeline from the Americas and cemented England's rise as the dominant Atlantic naval power.
Count Totleben vanished, leaving King Erekle II with just 3,000 men against an Ottoman army three times his size. They fought through scorching heat and mud at Aspindza, where hundreds of Georgians fell so their families wouldn't face the same fate. Yet they held the line until the sun set over the mountains. The victory bought them time, not peace, as Russia never truly returned to help. Today, you'll remember that sometimes the bravest thing isn't winning a battle, but standing alone when everyone else walks away.
A carriage full of strangers rolled through Grays Ferry, its wheels splashing mud while Washington sat stiffly inside. He wasn't a king; he was a man who'd just refused to wear a crown. Thousands lined the banks, their eyes wide with fear and hope, waiting to see if this experiment would work. The journey stretched on for days, a slow crawl toward New York where a new government waited. But the real weight wasn't in the title he accepted; it was in the choice to leave his home behind. That day, a farmer became a symbol of everything we'd become.
Napoleon personally directed a French assault that shattered two Austrian corps at Abensberg in Bavaria on the second day of a lightning four-day campaign. The emperor exploited gaps between the separated Austrian columns, routing them piecemeal before they could concentrate their superior numbers. The Abensberg victory set up the decisive Battle of Eckmuehl two days later, driving the Austrians back across the Danube and demonstrating Napoleon's mastery of rapid maneuver warfare.
He walked into Timbuktu disguised as an Afghan prince, shedding his European boots to survive. René Caillié was the second non-Muslim to enter the city after Major Laing, but while Laing never made it out, René did. He spent months surviving on millet and fear before dragging himself back to France. His survival proved the interior wasn't a death trap, sparking a frenzy of European exploration that followed his trail. Today, we remember not the map he drew, but the sheer will it took to pretend to be someone else just to live.
A beast with a monkey's voice strangled two women in Paris, yet no human suspect could explain how. Edgar Allan Poe didn't just write a story; he invented C. Auguste Dupin, a man who solved crimes by thinking harder than the police ever could. That single leap turned chaos into logic for readers everywhere. Now you'll tell your friends about the monkey that started it all.
Lee stood in his quarters, staring at two flags: the stars of the Union and the banner of Virginia. He didn't just resign; he burned his bridges with a single signature on April 20, 1861, handing over his sword to Jefferson Davis. That split tore apart families like his own—his brother-in-law Ulysses S. Grant now stood across the line from him at Appomattox. He chose blood over law, and the war began in earnest. You can't look at a family photo today without wondering who would have drawn a sword for which side.
A swan-necked flask, tilted like a drunken bottle, sat in Pasteur's lab while Bernard watched. They boiled broth for days, then left it open to the Paris air. Nothing grew. Life didn't pop into existence from dust; it traveled on invisible hitchhikers. This wasn't just a theory killed; it was a promise that sickness had a source we could actually fight. Now you'll tell everyone that your soup is safe not because it's clean, but because life only comes from other life.
A simple white disk dropped into Rome's Tiber turned the Pope's yacht into a floating lab. Secchi watched it vanish at 12 meters, proving water clarity could be measured by anyone with a bucket and patience. This moment cost nothing but a few seconds of time, yet it birthed a tool scientists still use today to track our dying oceans. We didn't just learn how clear the water was; we learned how much we were about to lose.
A single village named Batak became a slaughterhouse in May, yet the fire started back in April when local rebels decided to stop waiting for permission. Ottoman troops didn't just crush the resistance; they systematically killed over 5,000 men, women, and children who had nothing left to lose but their lives. This bloodbath shocked Europe so hard it forced Russia to declare war on the empire that held them captive for centuries. Today, when you see a Bulgarian flag, remember it wasn't drawn in peace treaties, but carved out of ash by people who chose death over silence.
Fun Facts
Zodiac Sign
Taurus
Apr 20 -- May 20
Earth sign. Patient, reliable, and devoted.
Birthstone
Diamond
Clear
Symbolizes eternal love, strength, and invincibility.
Next Birthday
--
days until April 20
Quote of the Day
“If you tell a big enough lie and tell it frequently enough, it will be believed.”
Share Your Birthday
Create a beautiful birthday card with events and famous birthdays for April 20.
Create Birthday CardExplore Nearby Dates
Popular Dates
Explore more about April 20 in history. See the full date page for all events, browse April, or look up another birthday. Play history games or talk to historical figures.