On Dec. 18, 1865, the 13th Amendment to the Constitution, abolishing slavery, was declared in effect.

In 1892, Tchaikovsky's ballet "The Nutcracker" publicly premiered in St. Petersburg, Russia.

In 1940, Adolf Hitler signed a secret directive ordering preparations for a Nazi invasion of the Soviet Union. (Operation Barbarossa was launched in June 1941.)

In 1956, the controversial movie "Baby Doll," starring Carroll Baker, was released.

In 1956, the panel game show "To Tell the Truth" debuted on CBS TV.

In 1969, Britain's Parliament abolished the death penalty for murder.

In 1972, the United States began heavy bombing of North Vietnamese targets during the Vietnam War. (The bombardment ended 12 days later.)

In 1996, FBI agent Earl Edwin Pitts was arrested, accused of selling secrets to the Russians. (Pitts was sentenced in June 1997 to 27 years in prison after admitting that he'd conspired and attempted to commit espionage.)

In 2001, a federal judge in Philadelphia threw out Mumia Abu-Jamal's death sentence and ordered a new sentencing hearing for the former Black Panther. (Both sides appealed that ruling, and Abu-Jamal remains on death row.)