In 2005, Jeffrey R. Collins put forward an Erastian interpretation of the English Revolution, arguing that Thomas Hobbes's ecclesiology was the most original product of the struggle 'by the state to crush the independence of the clerical estate'.1 Both in the Elements and De cive, and particularly in the Leviathan, Hobbes's theory of sovereignty was intended to equip the civil authority with a powerful instrument capable of responding to the Protestant claim for the role of the magistrate in protecting 'a body of revealed knowledge to which they were passionately committed', and with the humanist and Machiavellian conception of church and religion as instrumentum regni.2 If Erastianism, as a term used by Collins in a broad sense to denote the theory of the subordination of the church to the State, was the leit motiv of Hobbes's writings, what changed from De cive to the Leviathan was 'the proper relationship between temporal and spiritual authority'. In De cive, Hobbes assigned to Charles I the power to interpret Sacred Scriptures and to administer sacraments in order to curb the growing dualism between spiritual and temporal power which marked the Laudian reformation of the Anglican Church. In Leviathan, indeed, Hobbes's Erastianism condoned the religious settlement of the Independents, so that, during the 1650s, his doctrine of the subordination of the church to the State and his civil religion were partially adopted by a number of republican and Independent writers. Between 1654 and 1655, according to Collins, Hobbes was in tune with the Erastian politics of Cromwell and of his favourite minister, John Owen. Besides offending the Presbyterians, Hobbes's ecclesiology had as its most fierce opponents the post-Laudian Anglicans, Bramhall, Sheldon, Hammond, and Thorndike, who supported iure divino episcopacy and invoked dualism in State-church relations. The restoration of monarchy and of Anglicanism in 1660 marked the momentary decline of Hobbes's fortune and the success of his clerical adversaries. Nonetheless, particularly during the Interregnum, his political and religious doctrine embodied and fostered at the same time the protestant and humanist plan for a reformation of the church under the control of the State.To sum up, Jeffrey R. Collins interprets the English Revolution as primarily an Erastian struggle between the State and the clerical estate. Consequently, as the champion of Erastianism in the 1650s, Hobbes endorsed the church settlement made by Cromwell and the Independents, thus becoming the target of harsh criticism by Presbyterians and former Anglican bishops, who wished to restore the anti-Erastian Episcopal church of Laud.However, Collins's attempt to portray Hobbes as a key theorist of English Erastianism neglects the influence of the works of Hugo Grotius on the post-1649 debate on the relations between State, church, and religion. Unlike Hobbes, Grotius was during his life the author of more than fifty tracts on constitutional history, philology, natural and international rights, theology, ecclesiology, and politics. Students of the Dutch thinker have tended so far to focus on individual aspects of his work, favouring the study of juridical tracts such as De iure praedae commentarius and De iure belli ac pacis. There have also been studies on Grotius's theological works, such as Meletius, De veritate religionis christianae and De imperio, as well as on the historicconstitutional writings of his youth, like the Liber de Antiquitate Reipublicae Batavicae written in 1610 in support of the independence of the United Provinces from Spain3. What we lack, though, is an attempt to reassess the importance of the Dutch lawyer's thought by placing it in the broader context of European political and religious culture.Grotius was an heterogeneous thinker, who forged a moral and civil philosophy, as well as a theology, intended to lay the foundations of a new religious and political order of Christianity. …