April 12
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Featured Event
PhotoQuest—Archive Photos/Getty Images
Polio vaccine announced as “safe, effective, and potent”
On this day in 1955, the results of a two-year trial of a polio vaccine involving nearly two million children were presented at a press conference: it proved 80–90 percent effective in preventing polio, it greatly lessened the severity of disease in those who did contract it, and no inoculated children died. The vaccine, which had been developed by physician and researcher Jonas Salk, was licensed that same day, and production began immediately. It was the first step toward eradication of a disease that had been known for millennia. [Read today’s edition of Today in History > >]
Featured Biography
Featured Biography
Mary Evans Picture Library
Born this day in 1550, English lyric poet Edward de Vere, 17th earl of Oxford, emerged in the 20th century as the strongest candidate proposed (other than William Shakespeare himself) as the author of Shakespeare’s plays.
Famous Birthdays
More on April 12
Travel Bug/Shutterstock
2014
A forest fire swept into the port city of Valparaíso, Chile, destroying several thousand homes and claiming the lives of at least 16 people before it was extinguished several days later. [Sort fact from fiction in our quiz about Chile.]
© PA Images Archive/Getty Images
1989
Sugar Ray Robinson, a six-time world boxing champion considered by many to have been the best fighter in history, died at age 67. [Test your knowledge of boxing, basketball, and more.]
© Cheryl Chenet—Corbis Historical/Getty Images
1983
Harold Washington was elected the first African American mayor of Chicago. [Take our quiz about Chicago history.]
Encyclopædia Britannica, Inc.
1981
Joe Louis, the world heavyweight boxing champion from 1937 to 1949, died at age 66. [How much do you know about boxing?]
NASA
1981
NASA launched the first space shuttle, Columbia, which was designed to orbit Earth, transport people and cargo to and from orbiting spacecraft, and glide to a runway landing on its return to Earth. [Watch: how the space shuttle program did, and didn’t, deliver on its goals.]
Tass/Sovfoto
1961
Russian cosmonaut Yuri Gagarin became the first human in outer space. [Test your knowledge of famous astronauts and cosmonauts.]
Photo by Mass Communication Specialist 1st Class Chad J. McNeeley, U.S. Navy
1947
David Letterman, best known as the host of his long-running late-night talk show, was born in Indianapolis. [Take our pop culture quiz.]
UPI/Bettmann Archive
1945
U.S. President Franklin D. Roosevelt died at age 63. [Watch an overview of Franklin D. Roosevelt’s life and presidency.]
© Getty Images
1892
A patent for the first portable typewriter was issued in the United States. [Test your knowledge of inventors and their inventions.]
Library of Congress, Washington, D.C. (reproduction no. LC-DIG-ppmsca-32284)
1861
Fort Sumter, one of the few military installations in the South still in Federal hands, came under fire from Confederate guns in Charleston, South Carolina, thus initiating the American Civil War. [Watch: how the Battle of Fort Sumter unfolded.]
© North Wind Picture Archives
1777
Statesman Henry Clay, who sought to shield the country from sectional discord over slavery, was born in Hanover county, Virginia. [Sort fact from fiction in our quiz about famous Americans.]
Encyclopædia Britannica, Inc.
1606
The Union Flag, precursor to the Union Jack, was adopted as the national flag of Great Britain. [Test your knowledge of flags around the world with our crossword puzzle.]
Image: Encyclopædia Britannica, Inc.
1204
Alexius V, the last Greek emperor of a united Byzantium, fled Constantinople in the face of the Fourth Crusade. [Take our quiz about kings and emperors.]