Samuel Slater built the nation's first cotton mill in Pawtucket, R.I.
The United States purchased the Louisiana territory from France for $15 million.
South Carolina became the first state to secede from the Union.
Author John Steinbeck died at age 66.
The United States invaded Panama and installed a new government but failed to capture General Manuel Antonio Noriega.
Astronomer Carl Sagan died at age 62.