On March 21, 1844, the New England Baptist preacher William Miller had predicted the Second Coming. When the world had not ended the next day, he actually admitted an error in his calculations (a rare occurrence among eschatologists) and concluded that the apocalypse would take place on April 18.
When yet a third date failed - in what came to be called "The Great Disappointment" - the Millerites went on to form the Seventh Day Adventists in 1861.
