When Martin Luther hung his ninety-five theses on the church door in Wittenberg, the Roman Catholic Church suffered the greatest schism in its modern history. The result was Protestantism. What were the social, economic and religious conditions which gave rise to Protestantism? Who were thse men--Luther, Zwingli and Calvin--who initiated the tremendous division that is our heritage today? The author gives the answers to these questions and traces Protestantism through all the twists and turns of its history. Here are the insights into the thinking of the Reformers and their influence in central and northern Europe.