The document summarizes the birth of Protestantism in Europe in the 16th century. It details how corruption in the Catholic Church, including the selling of indulgences, led Martin Luther to post his 95 Theses criticizing these practices. Luther's views, which emphasized faith over works and interpreting the Bible independently, spread rapidly. Other reformers like John Calvin also worked to spread Protestant ideas throughout Europe, and by the end of their work over half of Europe had become Protestant.