The year 1517 marks the beginning of the Protestant Reformation, a major religious movement that aimed to challenge the Catholic Church's practices and beliefs. Initiated by Martin Luther when he posted his Ninety-Five Theses on the door of the Wittenberg Castle Church, the Reformation criticized the sale of indulgences and emphasized individual faith and scripture over Church authority. This movement led to the establishment of various Protestant denominations and significant changes in Christian doctrine. The Reformation not only transformed the religious landscape of Europe but also influenced cultural, social, and political developments, paving the way for greater religious freedom and personal conscience.