Who posted his Ninety-five Theses in Wittenberg in 1517, sparking the Reformation?

On October 31, 1517, Martin Luther, a German monk and professor, sent his Ninety-five Theses objecting to the sale of indulgences, and tradition holds that he nailed them to the door of the Castle Church in Wittenberg. The church door served as a sort of community bulletin board for academic debate.

Thanks to the new printing press, copies spread across Germany within weeks. Luther came to teach that salvation is by grace through faith alone, and that Scripture is the final authority for Christians.

Luther also translated the Bible into German so ordinary people could read it, and he wrote hymns for congregations to sing. Many Protestant churches still mark October 31 as Reformation Day.