The history of the Abbey of Cluny, founded in 910 west of Mâcon, and its monastic world is one of the classic themes in medieval studies. The monastery's undisputed leading role as a center of monastic reform until the early 12th century, the high esteem and political influence of its abbots, the magnificent building activities, and the unparalleled wealth of historical tradition have provided researchers with a rich field of study for over a hundred years. Hugh (I) of Cluny, also known as Hugh 'of Semur' due to his origins from a Burgundian noble family, was the sixth in the line of the famous abbots of Cluny. His sixty-year tenure began in 1049 and spanned almost the entire era of church reform and the Investiture Controversy until 1109. As the godfather of Henry IV, as a mediator between Gregory VII and Henry IV at Canossa, and as the builder of Cluny III, the largest church of its time, he has become known beyond the circle of historians interested in monasticism.