Harold Camping is certainly not the first to forecast the end of days. TIME takes a look at other movements that have scared people into believing their days were numbered The onset of World War I freaked a lot of people out. But it was especially trippy for the Zion's Watch Tower Tract Society, a group that's now called Jehovah's Witnesses. The society's founder, Charles Taze Russell, had previously predicted Christ's invisible return in 1874, followed by anticipation of his Second Coming in 1914. When WW I broke out that year, Russell interpreted it as a sign of armageddon and the upcoming end of days or, as he called it, the end of "Gentile times." History proved otherwise.
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