Adventism is a branch of Protestant Christianity that believes in the imminent Second Coming (or the "Second Advent") of Jesus Christ. It originated in the 1830s in the United States during the Second Great Awakening when Baptist preacher William Miller first publicly shared his belief that the Second Coming would occur at some point between 1843 and 1844. His followers became known as Millerites. After Miller's prophecies failed, the Millerite movement split up and was continued by a number of groups that held different doctrines from one another. These groups, stemming from a common Millerite ancestor, became known collectively as the Adventist movement. Although the Adventist churches hold much in common with mainline Christianity, their theologies differ on whether the intermediate state of the dead is unconscious sleep or consciousness, whether the ultimate punishment of the wicked is annihilation or eternal torment, the nature of immortality, whether the wicked are resurrected after the millennium, and whether the sanctuary of Daniel 8 refers to the one in heaven or one on earth. The movement has encouraged the examination of the whole Bible, leading Seventh-day Adventists and some smaller Adventist groups to observe the seventh day Sabbath. The General Conference of Seventh-day Adventists has compiled that church's core beliefs in the 28 Fundamental Beliefs (1980 and 2005), which use biblical references as justification. In 2010, Adventism claimed some 22 million believers scattered in various independent churches. The largest church within the movement—the Seventh-day Adventist Church—had more than 21 million members in 2020. History Adventism began as an inter-denominational movement. Its most vocal leader was William Miller. Between 50,000 and 100,000 people in the United States supported Miller's predictions of Christ's return. After the "Great Disappointment" of October 22, 1844, many people in the movement gave up on Adventism. Of those remaining Adventist, the majority gave up believing in any prophetic (biblical) significance for the October 22 date, yet they remained expectant of the near Advent (second coming of Jesus). Of those who retained the October 22 date, many maintained that Jesus had come not literally but "spiritually", and consequently were known as "spiritualizers". A small minority held that something concrete had indeed happened on October 22, but that this event had been misinterpreted. This belief later emerged and crystallized with the Seventh-day Adventist Church, the largest remaining body today. Albany Conference (1845) The Albany Conference in 1845, attended by 61 delegates, was