Caesarius of Heisterbach

Caesarius of Heisterbach (ca. 1180 – ca. 1240) (sometimes erroneously called in English Caesar of Heisterbach) was the prior of the former Cistercian monastery Heisterbach Abbey, in the Siebengebirge near the little town of Oberdollendorf, Germany.

He is best known as the compiler of a book of hagiography, the Dialogus miraculorum, which is a collection of 746 miracle stories arranged in 12 "distinctions." The tales are told in the form of dialogues between a monk and a novice. The work was often referred to by preachers seeking material for sermons in the Late Middle Ages. The work was popular and was widely distributed, showing that it catered well to the tastes of the times; it was perhaps the second largest late mediaeval best-seller, second only to the Golden Legend of Jacobus de Voragine. A vision reported in the book provided the source for the iconography of the Virgin of Mercy.