Martin Luther wrote the 95 Theses in 1517, which is often credited with initiating the Protestant Reformation. This document, which critiqued the Catholic Church's practices, particularly the selling of indulgences, sparked widespread debate and led to a significant split in Christianity. Luther's call for reform resonated with many, leading to the establishment of various Protestant denominations. The 95 Theses emphasized salvation through faith alone and the authority of Scripture, fundamentally altering the religious landscape of Europe and promoting individual interpretations of faith.