The Hammond Circus Train Wreck occurred on June 22, 1918, and was one of the worst train wrecks in U.S. history. Eighty-six people were reported to have died and another 127 were injured when a locomotive engineer fell asleep and ran his troop train into the rear of a circus train near Hammond, Indiana. The circus train held 400 performers and roustabouts of the Hagenbeck–Wallace Circus.

The Hagenbeck–Wallace Circus was a circus that traveled across America in the early part of the 20th century. At its peak, it was the second-largest circus in America next to Ringling Brothers and Barnum and Bailey Circus. It was based in Peru, Indiana.