By: HISTORY.com Editors

1940

Nazis begin killing “unfit” people in East Prussia

Published: November 16, 2009Last Updated: May 28, 2025

On May 21, 1940, a “special unit” carries out its mission and begins murdering more than 1,500 hospital patients in East Prussia. The massacre lasted until June 6, 1940.

Mentally ill patients from throughout East Prussia had been transferred to the district of Soldau, also in East Prussia. A special military unit, basically a hit squad, carried out its agenda and killed the patients over an 18-day period, one small part of the larger Nazi program to exterminate everyone deemed “unfit” by its ideology. After the murders, the unit reported back to headquarters in Berlin that the patients had been “successfully evacuated.”

Why the Nazis Were Obsessed With Twins

Horrifying medical experiments on twins helped Nazis justify the Holocaust.

By: Erin Blakemore

Timeline

Also on This Day in History

Discover more of the major events, famous births, notable deaths and everything else history-making that happened on May 21st

1539

Black Spanish explorer Estevan is reported killed

Word reaches Fray Marcos that Native Americans have killed his guide Estevan, a Black enslaved man who was the first non-Indigenous man to visit the pueblo lands of the American Southwest. Thought to have been born sometime around 1500 on the west coast of Morocco, Estevan was sold to the Spanish as an enslaved worker. […]

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1542

Spanish conquistador Hernando de Soto dies in American wilderness

On the banks of the Mississippi River in present-day Louisiana, Spanish conquistador Hernando de Soto dies, ending a three-year journey for gold that took him halfway across what is now the United States. In order that local peoples would not learn of his death, and thus disprove de Soto’s claims of divinity, his men buried […]

2:16m read

1683

World’s first university museum opens in Oxford, England

The Ashmolean, the world’s first university museum, opens in Oxford, England. At the time of the English Restoration, Oxford was the center of scientific activity in England. In 1677, English archaeologist Elias Ashmole donated his collection of curiosities to Oxford University, and the school’s directors planned the construction of a building to display the items […]

1:04m read

1758

Lenape tribe abducts Mary Campbell from western Pennsylvania

On May 21, 1758, Mary Campbell, believed to be ten years old, is abducted from her home in Cumberland County, Pennsylvania by members of the Lenape tribe; she becomes an icon of the French and Indian War. According to Indian Country Today, kidnappings of white women and children by Native American tribes were not uncommon during […]

2:04m read

1881

American Red Cross founded

Humanitarians Clara Barton and Adolphus Solomons found the American Red Cross, an organization established to provide humanitarian aid to victims of wars and natural disasters

1:04m read

1901

Connecticut enacts first speed-limit law

On May 21, 1901, Connecticut becomes the first state to pass a law regulating motor vehicles, limiting their speed to 12 mph in cities and 15 mph on country roads. Speed limits had been set earlier in the United States for non-motorized vehicles: In 1652, the colony of New Amsterdam (now New York) issued a […]

2:04m read

1911

French troops occupy Fez, sparking second Moroccan Crisis

Six years after the First Moroccan Crisis, during which Kaiser Wilhelm’s sensational appearance in Morocco provoked international outrage and led to a strengthening of the bonds between Britain and France against Germany, French troops occupy the Moroccan city of Fez on May 21, 1911, sparking German wrath and a second Moroccan Crisis. In March 1911, […]

2:16m read

1924

Leopold and Loeb murder Bobby Franks

On May 21, 1924, 14-year-old Bobby Franks is abducted from a Chicago, Illinois, street and killed in what later proves to be one of the most unusual murders in American history. The killers, Nathan Leopold and Richard Loeb, were wealthy and intelligent teenagers whose sole motive for killing Franks was the desire to commit the […]

2:40m read

1927

Charles Lindbergh completes the first solo, nonstop transatlantic flight

American pilot Charles A. Lindbergh lands at Le Bourget Field in Paris, successfully completing the first solo, nonstop transatlantic flight and the first ever nonstop flight between New York to Paris. His single-engine monoplane, The Spirit of St. Louis, had lifted off from Roosevelt Field in New York 33 1/2 hours before. Charles Augustus Lindbergh, […]

1932

Amelia Earhart becomes the first woman to make solo, nonstop transatlantic flight

Five years to the day that American aviator Charles Lindbergh became the first pilot to accomplish a solo, nonstop flight across the Atlantic Ocean, female aviator Amelia Earhart becomes the first pilot to repeat the feat, landing her plane in Ireland after flying across the North Atlantic. Earhart traveled over 2,000 miles from Newfoundland in […]

1:22m read

1942

Thousands of Jews deported from Chelm

On May 21, 1942, 4,300 Jews are deported from the Polish town of Chelm to the Nazi extermination camp at Sobibor, where all are later gassed to death. On the same day, the German firm IG Farben sets up a factory just outside Auschwitz, in order to take advantage of Jewish slave laborers from the […]

1:38m read

1956

United States drops hydrogen bomb over Bikini Atoll

The United States conducts the first airborne test of an improved hydrogen bomb, dropping it from a plane over the tiny island of Namu in the Bikini Atoll in the Pacific Ocean on May 21, 1956. (Because of the time difference, it was still May 20 in the U.S.) The successful test indicated that hydrogen […]

1:58m read

1960

Huge earthquake hits Chile

On May 21, 1960, the first tremor of a series hits Valdivia, Chile. By the time they end, the quakes and their aftereffects kill 5,000 people and leave another 2 million homeless. Registering a magnitude of 7.6, the first earthquake was powerful and killed several people. It turned out to be only a foreshock, however, […]

1:40m read

1992

“Long Island Lolita” is arrested

Amy Fisher, the so-called “Long Island Lolita,” is arrested for shooting Mary Jo Buttafuoco on the front porch of her Massapequa, New York, home. Fisher, only 17 at the time of the shooting, was having an affair with 38-year-old Joey Buttafuoco, Mary Jo’s husband. The tawdry story soon became a tabloid and talk-show fixture, the […]

1:18m read

1997

Avian flu kills young boy

A three-year-old boy dies of avian influenza in Hong Kong on May 21, 1997. By the time the outbreak was controlled, six people were dead and 1.6 million domestic fowl were destroyed. The young boy, the first victim of the flu outbreak, had been hospitalized six days earlier with severe coughing and fever. He had […]

2:14m read

1999

Soap star Susan Lucci wins first Emmy after 19 nominations

“The streak is over…Susan Lucci!” announces Shemar Moore of The Young and the Restless on this night in 1999, right before presenting the Daytime Emmy Award for Best Actress to the tearful star of ABC’s All My Children. The award was Lucci’s first win in 19 straight years of being nominated in the Best Actress […]

2:36m read

2000

Former president James Garfield’s spine put on display for final day

The exhibit featured medical oddities.

World War II

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