On this day 1521, Pope Leo X issued the papal bull ‘Decet Romanum Pontificem’ which excommunicated Martin Luther. Luther was a German monk who became disillusioned from the Catholic Church due to its corruption, such as taking money from people as a guarantee into heaven. Luther protested this corruption by famously writing his ‘95 Theses’ in 1517, an event which symbolically began the Protestant Reformation. The Pope did not accept Luther’s anti-Catholic writings and eventually expelled him from the church in 1521.
Luther’s excommunication finalised the split between Luther and his followers and the Catholic Church. The Protestant Reformation is one of the most important moments in European history, as it established the religious divide which shaped European history from 1517 onwards. Had it not been for the Reformation and the establishment of the Protestant Church the European wars of religion, and numerous other events, which raged in early modern Europe would not have occurred.