The Eastland was among the five boats transporting Western Electric workers with their families and friends to a park in Michigan City, Indiana, sailing across Lake Michigan.
With 2,500 people aboard, the SS Eastland turned onto its side over the Chicago River in July 1915, killing 844 people.
A hundred years passed after the boat upended, archival footage of the incident was unintentionally found by a graduate student recently.
The first-known footage of the Eastland disaster was discovered by Jeff Nichols, a doctoral student at the University of Illinois in Chicago, while scanning for unrelated material about World War I, the Chicago Tribune reported. Nichols explored the footage on Europeana’s 1914-1918 website.