Urban II (1042-1099) was pope from 1088 to 1099. He laid the foundations for the papal monarchy, and his pontificate marked a turning point in the institutional organization of the papacy and in papal-imperial relations.

Otto (or Odo) de Lagery, who became Urban II, was born near Châtillon-sur-Marne of a great French noble family. He grew up at Reims, where he became archdeacon, and at Cluny, where he became a monk and then prior. In 1078 Gregory VII created him cardinal bishop of Ostia. Loyally supporting Gregory's reforming ideals, he represented the Pope on numerous successful missions to France and Germany.

On March 12, 1088, Otto was elected pope and took the name Urban II. Though he was a convinced Gregorian, he was less fiery and passionate than Gregory VII and more politically astute about realizing a program of reform. Whereas Gregory VII had neglected the ties that bound the papacy...