The Protestant Reformation was a Christian movement in 16th-century Europe that formed out of opposition to perceived corruption and wrongdoing within the Roman Catholic Church. The reformation is popularly seen as beginning in 1517, the year when Martin Luther tacked his 95 Theses on the Power and Efficacy of Indulgences on the door of Castle Church in Wittenberg, Saxony. Historians contend that the movement ended in 1648 with the Treaty of Westphalia, which helped put an end to the bloody warfare that had raged on between Catholics and Protestants as a result of the Reformation period. The Reformation is seen as one of the most important events in Western history for its revolutionary exchange of ideas and political restructuring.
Theologians had argued against the Roman Catholic Church's view on the authority of the Pope prior to Luther's actions. In the 15th century, theologians John Wycliffe and John Huss argued that the Pope's authority wasn't valid according to the scriptures. Believing his views to be heretical, the Roman Catholic Church burned Huss at the stake in 1415.
Luther, a German Augustinian monk, posted his 95 Theses on the Power and Efficacy of Indulgences to communicate grievances he had with the Catholic Church and to invite debate with other Christians on theological matters. By the time he was preparing his arguments, many other Christians were also disgruntled with practices within the Roman Catholic Church, particularly the selling of indulgences. Indulgences were given out by priests, and offered remission of temporal punishment for sins for which the parishioner had already been forgiven.
Luther and other Protestant Christians didn't necessarily have an issue with the Catholic Church's doctrine of indulgences, but rather the way in which they were being sold for profit. Pope Leo X was in the midst of planning the construction of St. Peter's Basilica, and had allowed the selling of indulgences to raise funds for the building. This enraged Luther and others, who viewed penance and forgiveness as being crassly sold to the highest bidders.
Critics, including Luther, asked why the Pope didn't simply pay for the construction of St. Peter's Basilica himself since he was extremely rich. Luther also believed that grace and mercy came from faith alone, not by the buying and selling of indulgences. This belief came to be known as free grace theology.
Luther's 95 theses quickly spread through Germany and surrounding European nations, thanks in large part to the revolutionary use of the printing press. The monk was swiftly excommunicated by the Church, and the movement he represented was condemned by the Pope. Forced into hiding, Luther’s life may have been spared by Germany's Elector of Saxony, Frederick III, otherwise known as Frederick the Wise.
Frederick had for years played a pivotal role in Luther's life. He founded Wittenberg, the University where Luther taught and posted his theses, and protected the monk even though he remained a devout Catholic. Frederick believed Luther hadn't committed any actual crime, even if he wasn't sure about whether he ideologically agreed with the Protestant Reformation.
Luther's comments help bring other influential theologians to light. John Calvin, in particular, played a significant part in shaping the Protestant movement. He is perhaps best known for his doctrine of predestination, the belief that God has preordained who shall be saved by grace, and who will suffer eternal damnation. The theology is even more controversial than it is complicated, and it is one of the doctrines that Protestants had a difficult time agreeing on during the Reformation.
As the movement progressed throughout Europe, it began to splinter off into different factions. Ultimately, these factions gave rise to modern-day Protestant denominations such as Lutherans, Calvinists, and Presbyterians. The Reformation also gave way to bloody warfare between Catholics and Protestants, and the Thirty Years' War — which was really a series of wars — ravaged parts of Europe.
To end the fighting, the Treaty of Westphalia was created in 1648. It ended the Pope's political dominance over Europe and provided some leniency for different Christian factions to practice their faith. Ultimately, in the way that it led to an entirely new political structure in Europe, and in the way it revolutionized Christianity, the Protestant Reformation stands as one of the seminal events in Western history.