This legend takes place around the year 1200. Back them, many knights from the Rhineland taken the cross and followed Emperor Friedrich I. Barbarossa to Palestine. Some of them had not come back yet.
It was at the beginning of the Middle Ages. The Roman Empire, that had long become unruleable, had broken down under the attack of the migration of the peoples. It was a time of turmoil, and the people lived in constant fear of being attacked by other tribes.
The Monastery of Heisterbach is situated in a beautiful valley below the Petersberg. In those days, the monks spent their days praying and working. One of them often wondered about the psalm saying that “to the Lord, a thousand years are like one day”, without understanding its full meaning.