On this day: December 20

1803: The Louisiana Purchase is completed as the territory is formally transferred from France to the United States during ceremonies in New Orleans.

1812: Sacagawea, a Native American member of the Lewis and Clark Expedition, dies of an unknown sickness at Fort Manuel Lisa Trading Post on the Missouri River about 12 miles north of what would become Omaha, Nebraska.

1860: When it becomes clear that Abraham Lincoln would be the next president, South Carolina becomes the first state to declare its secession from the Union.

1868: Automobile pioneer Harvey Firestone, the founder of the Firestone Tire and Rubber Company, is born in Columbiana, Ohio.

1879: Thomas Edison privately demonstrates his incandescent light at Menlo Park, New Jersey.

1881: Branch Rickey, the baseball executive famous for creating the farm team system and hiring the first black players, including Jackie Robinson with the Brooklyn Dodgers, is born in Stockdale, Ohio. The Baseball Hall of Famer died of heart failure at age 83 on Dec. 9, 1965.

1922: Film director George Roy Hill (left), best known for such films as "Butch Cassidy and the Sundance Kid," "The Sting," "The World According to Garp" and "Slap Shot," is born in Minneapolis, Minnesota. Hill, seen here with sound engineer William Edmondson on the set of "Butch Cassidy and the Sundance Kid," died at age 81 from complications of Parkinson's disease in December 2002.

1924: Adolf Hitler is released from Landsberg Prison after being pardoned early. He was serving a five-year sentence for an attempted 1923 coup, but served a little more than a year.

1946: The Frank Capra film "It's a Wonderful Life," starring James Stewart and Donna Reed, has a preview showing for charity at New York City's Globe Theatre, a day before its official world premiere. The film was nominated for five Oscars and has been recognized by the American Film Institute as one of the 100 best American films ever made.

1957: Elvis Presley receives his U.S. Army draft notice. In January 1958 he was granted a deferment to finish the forthcoming movie "King Creole," and would be inducted into the U.S. Army as a private on March 24, 1958.

1963: The Berlin Wall is opened for the first time to West Berliners, who are allowed one-day visits to relatives in the Eastern sector during the Christmas season. Similar, very limited arrangements were made in 1964, 1965 and 1966.

1968: American writer John Steinbeck, the Nobel laureate and Pulitzer Prize-winning author of novels such as "The Grapes of Wrath" and "Of Mice and Men," dies of heart disease and congestive heart failure at the age of 66 in New York City.

1968: The Zodiac Killer shoots and kills teenagers Betty Lou Jenson and David Faraday in Benicia, California. Although law enforcement authorities suspect the serial killer may have begun as early as 1963, Jenson and Faraday are his first confirmed victims. The serial killer, whose identity remains unknown, is responsible for killing at least five people and injuring two more, but could be responsible for up to 37 murders. Pictured is a police sketch of the Zodiac Killer.

1973: Singer and actor Bobby Darin, best known for the songs "Splish Splash," "Dream Lover", "Mack the Knife" and "Beyond the Sea," dies at the age of 37 at Cedars-Sinai Medical Center in Los Angeles after undergoing surgery to repair two artificial heart valves he had received in January 1971.

1976: Chicago Mayor Richard J. Daley suffers a massive heart attack while visiting his doctor's office and dies at the age of 74. Daley, seen here applauding at right during the 1976 Illinois State Democratic Convention in Chicago, served for 21 years as the mayor and undisputed Democratic boss of Chicago and is considered by historians to be the "last of the big city bosses."

1987: The passenger ferry Doña Paz sinks after colliding with the oil tanker Vector 1 in the Tablas Strait in the Philippines. Upon the collision, the Vector's cargo ignited and caused a fire on the ship that spread onto the Doña Paz. Both ships then sank into the flaming waters of the shark-infested strait. Only 26 people were rescued from the two ships, with the official death toll placed at 1,749. However, survivors said the ferry was overloaded with passengers and that the toll could actually be between 3,000 and 4,000. Either way, the collision stands as the deadliest peacetime maritime disaster in history. The Doña Paz is seen here in 1984.

1989: The United States sends troops into Panama to overthrow the government of Gen. Manuel Noriega in a mission code-named Operation Just Cause. This is also the first combat use of purpose-designed stealth aircraft, the F-117A Nighthawk. Noriega remained at large for several days but eventually took refuge in the Vatican diplomatic mission in Panama City. He finally surrendered to the U.S. military on Jan. 3, 1990, and was immediately flown to the United States.

1995: NATO begins a peacekeeping mission in Bosnia. The troops were used to enforce the Dayton Peace Agreement, which brought an end to three and a half years of war in Bosnia and Herzegovina.

1996: American astronomer and writer Carl Sagan, known for his popular science books, including the novel "Contact," and for the award-winning 1980 television series "Cosmos: A Personal Voyage," which he narrated and co-wrote, dies of pneumonia at the age of 62 in Seattle, Washington.

1999: Canadian-American singer-songwriter and guitarist Hank Snow, who charted more than 85 singles on the Billboard country charts from 1950 until 1980, dies of heart failure at age 85 in Madison, Tennessee. Among Snow's hit songs were the No. 1 country hits "I'm Moving On," "The Golden Rocket," "I Don't Hurt Anymore," "Let Me Go, Lover!," "I've Been Everywhere" and "Hello Love."

2002: U.S. Sen. Trent Lott resigns as Senate Republican leader two weeks after igniting a political firestorm with racially charged remarks at Sen. Strom Thurmond's 100th birthday party regarding Thurmond's 1948 presidential campaign. Thurmond had run as a Dixiecrat on an explicit States' Rights platform that challenged the Civil Rights Movement and called for the preservation of racial segregation.

2007: Queen Elizabeth II becomes the oldest ever monarch of the United Kingdom, surpassing Queen Victoria, who lived for 81 years, 7 months and 29 days.