Happy Reformation Day!

Luther, Zwingli, and Calvin

The Protestant Reformation was a movement in Europe that began with Martin Luther's activities in 1517 and ended with the Peace of Westphalia in 1648.[1] The movement began as an attempt to reform the Catholic Church and led to the fracturing of Christendom. Many western Christians were troubled by what they saw as false doctrines and malpractices within the Church, particularly involving the teaching and sale of indulgences. Another major contention was the practice of buying and selling church positions (simony) and the tremendous corruption found at the time within the Church's hierarchy. This corruption was systemic at the time, even reaching the position of the Pope.[2]
On 31 October 1517, in Saxony (in what is now Germany), Martin Luther nailed his Ninety-Five Theses to the door of the Wittenberg Castle Church, which served as a pin board for university-related announcements. These were points for debate that criticized the Church and the Pope. The most controversial points centered on the practice of selling indulgences and the Church's policy on purgatory. Luther's spiritual predecessors were men such as John Wycliffe and John Hus. Other reformers, such as Ulrich Zwingli and John Calvin, soon followed Luther's lead. Church beliefs and practices under attack by Protestant reformers included purgatory, particular judgment, devotion to Mary, the intercession of the saints, most of the sacraments, and the authority of the Pope.
The most important Protestant groups to emerge directly from the reformation were the Lutherans, the Reformed/Calvinists/Presbyterians, the Anabaptists, and the Anglicans. Subsequent Protestant denominations generally trace their roots back to the initial Reformation traditions. It also accelerated the Catholic or Counter Reformation within the Roman Catholic Church.
The Protestant Reformation is also referred to as the "Protestant Revolution", "Protestant Revolt", and, in Germany, the "Lutheran Reformation". (From Wikipedia)