During the ninth and tenth centuries, the local church had come under the control of kings and feudal lords, who chose priests and bishops in their territories, granting them land and expecting loyalty and service in return. Church offices were sources of income as well as positions of authority. Officeholders had the right to collect taxes and fees and often to the profits from the land under their control. Church offices were thus sometimes sold outright — a practice called simony (SIE-muh-nee). Not surprisingly, clergy at all levels who had bought their positions or had been granted them for political reasons provided little spiritual guidance, and their personal lives were rarely models of high moral standards. Although the Roman Church officially required men to be unmarried in order to be ordained, there were many married priests and others simply living with women. Popes were chosen by wealthy Roman families from among their members, and after gaining the papal office, they paid more attention to their families’ political fortunes than to the health of the church.

Serious efforts to change all this began under Pope Leo IX (pontificate 1049–1054). Leo ordered clergy in Rome to dismiss their wives and invalidated the ordination of church officials who had purchased their offices. Pope Leo and several of his successors believed that secular or lay control over the church was largely responsible for its lack of moral leadership, so in a radical shift they proclaimed the church independent of secular rulers. The Lateran Council of 1059 decreed that the authority and power to elect the pope rested solely in the college of cardinals, a special group of priests from the major churches in and around Rome.

Leo’s successor Pope Gregory VII (pontificate 1073–1085) was even more vigorous in his championing of reform and expansion of papal power. He denounced clerical marriage and simony in harsh language and ordered excommunication (being cut off from the sacraments and all Christian worship) for those who disagreed. He believed that the pope was the vicar of God on earth and that papal orders were thus the orders of God. Gregory was particularly opposed to lay investiture — the selection and appointment of church officials by secular authority. In February 1075, he held a council at Rome that decreed that clerics who accepted investiture from laymen were to be deposed and laymen who invested clerics were to be excommunicated.

In the late eleventh century and throughout the twelfth and thirteenth centuries, the papacy pressed Gregory’s campaign for reform of the church. The popes held a series of councils, known as the Lateran Councils, that ratified decisions ending lay investiture, ordered bishops to live less extravagantly, and ordered married priests to give up their wives and children or face dismissal.

Gregory’s reforms had a profound effect on nuns and other women in religious orders. The movement built a strict hierarchical church structure with bishops and priests higher in status than nuns, who could not be ordained. The double monasteries of the early Middle Ages were placed under the authority of male abbots. The reformers’ emphasis on clerical celibacy and chastity led them to portray women as impure and lustful. Thus, in 1298, in the papal decree Periculoso, Pope Boniface VIII ordered all nuns to be strictly cloistered, that is, to remain permanently inside the walls of the convent, and for visits with people from outside the house, including family members, to be limited.