Millerism is a religious movement that emerged in the early 19th century, founded by American preacher William Miller. He predicted that the second coming of Jesus Christ would occur on October 22, 1844. Miller's interpretations of biblical prophecies, particularly from the Book of Daniel, led him to believe that this date was significant for the end of the world. When the predicted event did not occur, it resulted in what is known as the "Great Disappointment." Despite this setback, Millerism laid the groundwork for the formation of several new religious groups, including the Seventh-day Adventist Church, which continues to hold beliefs about the imminent return of Christ.