Karl Barth (1886-1968) is generally acknowledged to be the most important European Protestant theologian of the twentieth century, a figure whose importance for Christian thought compares with that of Augustine, Thomas Aquinas, John Calvin, Martin Luther, and Friedrich Schleiermacher. Author of the Epistle to the Romans, the multi-volume Church Dogmatics, and a wide range of other works - theological, exegetical, historical, political, pastoral, and homiletic - Barth has had significant and perduring influence on the contemporary study of theology and on the life of contemporary churches. In the last few decades, his work has been at the centre of some of the most important interpretative, critical, and constructive developments in in the fields of Christian theology, philosophy of religion, and religious studies.