On this date in history: In 1918, an empty troop train rear-ended the Hagenbeck-Wallace Circus train in Ivanhoe, Ind., killing 53 circus performers and many animals. The circus train had stopped to fix its brakes. In 1940, France fell to Germany in World War II. Nazi and French leaders signed the second armistice at Compiègne, France, in Ferdinand Foch's Railway Car. In 1941, Germany invaded the Soviet Union. In 1973, U.S. President Richard Nixon and Soviet leader Leonid Brezhnev signed a pledge to try to avoid nuclear war. In 1977, former U.S. Attorney General John Mitchell entered a federal prison...