
By the 10th Century, the church had fallen into what is known as “lay control,” in which lay people who were neither ordained nor were church officials began to rule the church. Partly being caused by feudalism, local lords chose their own abbots, bishops, and priests. Thus, these newly appointed clergy were often promoted for non-religious or political reasons.
The reform was named after Pope Gregory VII, who served as pope from 1073-1085. Around this time, monastic discipline had badly deteriorated because of undisciplined monks being allowed into monasteries. One of the first major steps for reform was the creation of the Cluny monastery in 910 in Burgundy, France. Established by a lay person, Duke William of Aquitaine, he said that he had no control over it and gave up authority to the Church. Becoming a center of reform, Cluny helped improve other monasteries and also affiliated with other ones as well.
When aristocratic families began jockeying for control of the Papacy, Pope Leo IX (1049-1054) was named to the Papal office by the emperor. Despite being recommended by a lay-person, Leo started reforming many Church abuses like Simony (the act of purchasing church offices) and clerical marriages. The office of cardinals who were advisors to the Pope was also established around this time by Pope Nicholas II.
Although Pope Gregory VII continued the reform, it slowed down by the late 1000s, since he couldn’t appoint his own people because monarchs and lords didn’t listen to him. Therefore Gregory proclaimed that the king’s role was to establish peace and order so people could pursue a Christian journey, while the Pope’s role was to teach the rules of the Church and choose clergy. Continuing, Gregory asserted that the Pope could excommunicate and depose kings as well. In 1075, Gregory held a council in which all clerics appointed by laymen were deposed and all the lords who appointed them were excommunicated, even kicking out King Henry IV of Germany, who ultimately submitted when faced with rebellion.