The Protestant Reformation began in 1517 when Martin Luther nailed his 95 Theses criticizing the Catholic Church's practices, such as selling indulgences, to a church door in Wittenberg, Germany. Luther's criticisms, aided by the spread of his ideas through the printing press, opened people's eyes to corruption and malpractices in the Catholic Church. When Luther refused to recant his criticisms at the Diet of Worms in 1521, he was excommunicated from the Church and went into hiding. This led to the formation of new Protestant churches that broke away from the Catholic Church's authority based on their own beliefs, such as Lutheranism, Calvinism, and Anglicanism.