A variety of causes contributed to the reformation which can be conveniently studied under the following heads:
1. Religious Causes:
In the first place, on the eve of reformation the church suffered from numerous evil practices which greatly undermined the reputation of the church and the churchmen. The entire organization of the church right from Pope down to the priest were corrupt and vicious. They neglected their dioceses and took keen interest in politics. Some of the clergy men had amassed huge wealth and were living a luxurious life.
They often indulged in hunting expeditions and drinking parties and completely neglected their religious duties. In short the church consisted of 'unholy men in holy orders'. Often the churchmen used the church as a means of business. They had devised a number of practices for this purpose. Thus the church office were openly sold and quite often unsuitable men were appointed as priests.
These people tried to make as much money as possible and liberally issued indulgences or pardon certificates against payment. This practice of issue of indulgences invited severe criticism and was described as 'sale of licenses to commit sin'.
The common masses were also unhappy with the Pope and church. They were not only unhappy with the prevailing corrupt practices in church and the flimsy grounds on which the church collected funds from innocent people but also disliked its interference in the secular affairs.
No wonder they were eagerly looking for someone to provide them a lead for a revolt against the church. Even the rulers were quite unhappy with the Pope and strongly protested against Papal interference in the affairs of their states. Hence they were willing to provide support to any movement which was launched against the authority of the Pope.
2. Economic Causes:
The emergence of a strong middle classes also greatly contributed to the reformation. The middle classes protested against the dominance of the old church because it was largely controlled by the upper classes and administered largely for their benefit. They looked down upon the artisans, merchants, lawyers, doctors etc. who constituted the middle class and were not willing to associate with them.
Further, these middle classes greatly resented the practice of exempting the nobles from taxation, while they had to bear the brunt of taxation. In short the middle classes wanted to free the church from the control of wealthy aristocracy which looked down upon them and cared very little for their interests.
Further, even the princes of Europe were not quite happy with the Pope who claimed considerable amount of their revenue in the form of annates and other contributions. The common people were also quite unhappy with the clergy which made numerous vexatious demands and hardly gave anything in return for their money.
3. Political Causes:
The rise of nation-states and new monarchy who were keen to establish their absolute rule, also greatly contributed to the Reformation. A number of monarchs like Henry VIII considered the presence of a powerful church as a serious check on their authority because it was in many ways outside the King's authority and the property of the church was exempted from royal taxation.
Further the Bishops still administered justice in church in accordance with the Canon Law. The flow of enormous amounts of money from the revenues of the country to the Papal treasury was also disliked by them. No wonder these kings fully exploited the opportunity offered by the teachings of Luther, Wycliffe etc. to challenge the authority of the church with a view to strengthen their own authority in the country.
They established Protestant churches in their country knowing it fully well that the new church would be dependent upon them and shall be willing to accept their political authority. Thus Protestant churches were established in many German principalities, in Holland, Denmark, Sweden, Norway and England.
4. New Learning and Spirit of Enquiry:
The new spirit of learning and enquiry set in motion by the renaissance also greatly contributed to the Reformation. People began to assert themselves against blind faith and useless religious rituals and began to feel that they could reach God without the intermediary of a priest.
Their reason also made them highly critical of the prevailing practices of sale of indulgences (pardon certificates), non-enforcement of the code of morality among the clergy, and undue interference of Papacy in the secular affairs.
5. Schism in Church:
The Schism in church in the fifteenth century also greatly lowered its prestige. Instead of one Pope, two Popes began to be elected one by the French Cardinals and the other by the Italian Cardinals.
This undermined the prestige of Pope and people lost faith and reverence for the holy institution. How could people serve two masters? The things were further complicated in 1409 when the cardinals at a joint sitting elected a third Pope. This is known as the Great Western Schism.
No doubt this Schism was bridged when the Council at Constance deposed both the Popes and elected a new Pope. But these developments certainly undermined the powers and prestige of the church.