History

The impeachment trial of President Andrew Johnson in the Senate on March 13, 1868. The House approved 11 articles of impeachment against Andrew Johnson. After a 74-day Senate trial, the Senate acquitted Johnson on three of the articles by a one-vote margin each and decided not to vote on the remaining articles. Library of Congress/Getty Images hide caption

The view of the Grand Canyon from the top floor of Desert View Watchtower on the southeastern rim. Eleven tribes have traditional ties to the Grand Canyon. Laurel Morales/KJZZ hide caption

Dennis Christensen, a Danish Jehovah's Witness accused of extremism, is escorted into a courtroom to hear his verdict in the town of Oryol on Feb. 6. Mladen Antonov/AFP/Getty Images hide caption

U.S. soldiers direct traffic outside the residence of the Peruvian ambassador to Panama, right rear, in Panama City on Jan. 9, 1990. In December 1989, U.S. President George H.W. Bush sent thousands of troops to Panama to arrest the country's leader, Manuel Noriega. John Gaps/AP hide caption

Artificial flowers decorate barbed wire fence as Soviet army troops stop in Kabul, Afghanistan, in May 1988. The Soviet Union invaded Afghanistan in December 1979 to shore up the pro-Soviet regime in Kabul. Douglas E. Curran/AFP/Getty Images hide caption

South Korean children shield their ears and mothers their babies as they watch U.S. 105mm howitzers blast enemy positions across the Han River. The attack occurred during their drive from the captured city Gimpo toward Seoul in Sept. 24, 1950. FRANK NOEL/AP hide caption

An enormous portrait of George Washington hangs alongside swastika banners and American flags at New York's Madison Square Garden in 1939 during the German American Bund's Pro American Rally. Field of Vision hide caption

Stephen Stills (left) performs with Buffalo Springfield on The Smothers Brothers Comedy Hour in 1967. CBS Photo Archive/CBS via Getty Images hide caption