By founding monasteries—as Duke William did at Cluny—the landowning warrior classes of Europe could effectively offset their sins by paying for monks to beg forgiveness their behalf in the form of masses.* The result was that from the ninth century onward, founding, endowing, or donating to monasteries became a popular pastime for rich men and women. And like all rich-people pastimes throughout history, it quickly became the object of fashion, competition, and one-upmanship.
