The Four Horsemen of the Apocalypse are biblical figures that represent different aspects of the apocalypse:

Conquest: The white horse represents religious deception and conquest

War: The red horse represents war

Famine: The black horse represents famine. The horseman carries weighing scales, which represent how bread was weighed during a famine

Death and pestilence: The pale horse represents pestilence, or disease epidemics and pandemics, and death

The Four Horsemen appear in the Book of Revelation, and are revealed when the first four of the seven seals are unsealed.