This book describes the close relationship between the historical researches and the teeming world of early nineteenth-century controversy. The setting is Oxford between the 1820s and the 1840s, when Newman made his ambitious and doomed attempt to re-invent the ‘catholicity’ of the Church of England. The author shows that in Newman’s battle against the Protestant wing of the Church of England, and the (to him) even more sinister ‘liberals’, he saw parallels with the struggle of the early Church against heresy. Newman’s ‘rediscovery’ of ancient Patristic writers and heretics was thus part of a strategy to revive Catholicism within the Anglican Church. Dr Thomas shows how Newman’s eventual conversion to Rome in 1845 may be understood as a change in his perception of heresy, and a realisation of the applicability of his own polemic to his Anglican self.