Conquest, War, Judgement, and Death
The scene illustrates the passage in The Revelation of Saint John wherein Judgement Day is prophecied. The first rider,
on the white steed of conquest, is farthest to the right. The second rides the red roan horse of war, the third the black horse of famine. The fourth, closest to the viewer, rides the pale horse of death. These four were given authority over one quarter of the earth to kill with bow, sword, famine, plague and the wild beasts of the earth. This scene, and uncertain medieval security (when the sound of horses at night was the sound of an attack) illustrate why terrifying dreams have long been called “nightmares”. 
 
After a woodcut by Albrecht Durer, Nuremberg, circa 1496.
Extensively redrawn fine art replica giclée print. © 1993, 1997 Allen Bjorkman.