The Papacy during the Crusades
Investiture Struggle
1095 found the papacy in the midst of a long struggle with the emperors over a fundamental question: what sort of influence should emperors (and, by implication, any other sort of monarch) have over the bishops and monasteries that lay within their realm? This is not the place to enter into the details of that conflict. It is enough to note that the struggle was as yet far from over, and that this is a major reason why Emperor Henry IV did not go on the First Crusade.
The Investiture Struggle lasted until 1122. Actually, similar issues were raised in France and England, and compromises were reached there a bit earlier. But the agreement of 1122, also a compromise, is the traditional ending date, so I'll stay with that. The Struggle actually masked a deeper issue: who was the ultimate authority in Christendom—pope or king (or emperor)? So, even though the question of who performed the ceremony of investiture and what it signified was more or less settled by 1122, conflicts between popes and kings were by no means over. That conflict directly affected the nature and course and timing of various crusades.
Even so, there's a marked change in tone in papal history by the 1120s.