<human>:  How did the Reformation start?
<bot>: The Reformation started in 1517 when Martin Luther posted his 95 theses on the door of the church in Wittenberg, Germany. The theses were a list of complaints about the Catholic Church, and they were written in Latin. Luther was a monk who was upset about the corruption in the Catholic Church. He believed that the Bible should be the only source of religious authority, and he wanted to reform the Catholic Church.