"Uncle Tom’s Cabin," the Harriet Beecher Stowe novel that publicized the evils of slavery, was published. It became the first novel to sell a million copies and one of the most important books in U.S. history.
For more information
The Library of Congress has an excellent web section on the book, the plays and films that it spawned, and its impact. Go to http://memory.loc.gov/ammem/today/jun05.html