Huldrych Zwingli (1484-1531) is one of the founders of Reformed Protestantism, whose effects extend far beyond Zurich. Zwingli's achievements can only be understood through the interaction of theological thought and social circumstances. Therefore, the author places particular emphasis on presenting Zwingli's theological thinking and on describing the political, ecclesiastical, and social conditions, as well as their changes during the Reformation. With his consistently historical approach, he overcomes the alternative between an apologetic or polemical portrayal of Zwingli. In an afterword, church historian Martin Sallmann characterizes the significance of this book, provides an overview of the literature published since the first edition in 1983, and thus brings this standard work up to date with current research.