Heinrich Bullinger (July 18, 1504-17 September 1575) was a Swiss reformer, Ulrich Zwingli successor as head of the Zurich church and pastor in the Minster. Figures are far less controversial figure than John Calvin or Martin Luther, where its role has long been underestimated. Recent research shows that he is one of the most influential theologians of the Protestant Reformation in the 16th century.