The Four Horsemen of the Apocalypse are described in the last book of the New Testament of the Bible, the Book of Revelation by John of Patmos, at Revelation 6 (6:1–8), according to the main exegetical stream since the Reformation. The chapter tells of a book or scroll in God's right hand that is sealed with seven seals. The Lamb of God opens the first four of the seven seals, which summons four beings that ride out on white, red, black, and pale horses. Before the Reformation it was generally thought that there was only one Horseman, riding successively these four horses.

Though theologians and popular culture differ on the first Horseman, the four riders are often seen as symbolizing Conquest or Pestilence (and less frequently, the Christ or the Antichrist), War, Famine, and Death. The Christian apocalyptic vision is that the Four Horsemen are to set a divine apocalypse upon the world as harbingers of the Last Judgment.

That the number of horsemen are four is important: four is the number associated with creation or the earth in the Book of Revelation. On the significance of fours in Revelation, see Biblical numerology.

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