This revised doctoral dissertation makes a strong case for the contemporary relevance of Augustinian political thought, despite the reservations of many intellectuals of the last century, which arose especially from Augustine's doctrine of sin and his focus on the hereafter. Gregory argues that Augustinians should not flee politics and that liberals should not shun Augustinianism. Furthermore, Augustinian liberals must not avoid Augustinian theology, which is the only way properly and fully to understand Augustine's conception of love which is not an obstacle but instead the key to balancing Christian civic life with Christian eschatology. The result is what Gregory calls Augustinian civic liberalism. His book develops this political theology primarily by tracking Augustine's reception in twentieth-century philosophy and political theory. Gregory judiciously appraises the diverse reasons a wide range of authors have found for accepting, qualifying, or rejecting aspects of Augustinian thought, especially Hannah Arendt and her 1929 dissertation, Der Liebesbegriff bei Augustin. Gregory's subject, therefore, is not the historical Augustine but what Augustine can offer people today. He even imagines what Augustine would make of the present world and its troubles. But Gregory is also a good reader of Augustine not only on his own terms but also in his own context, and it is exciting for the historian to read along with him. Gregory makes use of English-language historical studies, above all the work of Robert Markus – ‘the scholarly lodestar for Augustinian liberalism’ – but also that of Peter Brown, John Cavadini, Catherine Conybeare, Robert Dodaro and others. He also offers his own interpretations of texts outside De civitate dei 19, the locus classicus for political philosophy: in this respect his effort is related to that of Charles Matthewes's A theology of public life (Cambridge 2007). Given what seems to be a growing interest in late ancient and medieval emotions, the fifth chapter, on passions and Stoicism, may be the most immediately useful for historians. With both sensitive readings and a refined awareness of Augustine's intellectual development over the course of his life, Gregory demonstrates that lexical analysis and psychoanalytical theory will only go so far towards comprehending how Augustine understood emotions and their proper order. If they wish to understand the relationship of Augustine's thought to the secular world, Gregory might insist, then historians, as much as the political philosophers who are his main audience, must appreciate the way in which Augustine referred all to God. Finally, then, although his book does not aim for historical objectivity and instead advocates present civic engagement, Gregory offers historians an invigorating return to many of the most significant questions that Augustine posed for many generations to follow.