The Speak, Memory of late antiquity – Augustine’s Confessions – begins without speech, without memory. The North African bishop opens his spectacular book of self-reckoning with a sequence of thoughts on his own infancy in the AD 350s, during the reign of one of Constantine’s over-zealous sons. How did his life begin, he asks? And what came before it? ‘I don’t know’, he concludes. And this is the state of ignorance – the state of self-forgetting – in which every life begins.

This is significant. Augustine opens his Confessions by brooding on a period that his mother, Monnica, would have told him about, before she died in the late 380s in the Italian port-city of Ostia. His great work of memory does not begin with his memory, then, but with hers – and towering over both, he believes, are a past and future which have always already fused into the divine Present.

Kate Cooper is beautifully attuned to the fact that it is not only the secrets of Augustine’s beginnings that are shared by a woman in his life, and by his God. (The bishop rhythmically addresses God in that way – ‘my God’, Deus meus.) We know something of the dramatic presences of several women in Augustine’s life – and their still more dramatic absences – because he tells us. Yet Cooper seems to be the first historian to have asked, in a sustained and systematic way, exactly what he tells us – and what, beyond that, we can infer or conjecture.

Cooper’s book is a heady, highly readable blend of history and what we might call conjectural history (with a nod to one of Immanuel Kant’s essays). She does not confine herself to what Augustine tells us about the women who shaped his life. In the case of Augustine’s lover of many years (and mother of his only son), and his extremely young fiancée in Milan (who never shared his bed), we do not even know their names. What is there, then, to say about them?

If Cooper were a less accomplished historian of late-classical marriage and virginity, or a less sensitive reader of Augustine’s works, her account of what he tells us and might not tell us about the women God placed in his life – or so he certainly believed – might raise more questions than it settles. But Cooper never fails to signal when she is reading Augustine’s texts – or drawing judicious, often novel inferences from them – or finally imagining what sorts of figures and social configurations might well have stood behind the lines he left us.

Cooper is right to remind us that Augustine’s ‘work as a Christian pastor meant that women were never far from his thoughts’. His writings, most of which were composed when he was bishop in a prosperous African port-city, support this. More striking is her double claim that ‘Augustine was a man who noticed women’, and that he ‘not only noticed’ them but ‘explored in depth what he learned from them’. Queens of a Fallen World bears out both claims.

The first woman that Augustine notices, then, is his mother. Cooper’s chapter on Monnica highlights her Berber ancestry, and draws attention to a childhood memory that she evidently shared with her children – and which Augustine, in turn, shares with us. It is a seemingly minor incident. Monnica, still a young girl, is sipping wine on the sly in her father’s house. A nameless enslaved girl, whom Cooper calls Illa (from the Latin illa, ‘she’), sees this and dares to criticise it. Monnica accepts the other girl’s rebuke. She changes her habits, and never forgets the encounter.

We only know about this little childhood drama because it figures in Augustine’s Confessions. Cooper is right to ask: why is this glimpse of two girls in a provincial household important for the philosopher-bishop? She is right to conclude that he must have learned something from it. And what idea might be captured in this ‘thought-picture’? For Cooper, it is that truth can be revealed through a ‘person with lower social status’. She calls this – hyperbolically, but not emptily – ‘Illa’s legacy’ in Christian and European history.

Cooper’s fresh reading of Monnica’s childhood memory leads her to offer a powerful new reading of Augustine’s break with a ‘low-status’ lover of many years, whom he loved. ‘My heart had fused with hers’, he tells us. He does not, however, tell us her name: Cooper calls her Una (from the Latin una, ‘one’). Whatever her name may have been, this is what Augustine writes in a critical paragraph of Confessions 6:

The woman I’d been accustomed to sleeping with was torn from my side, because she was supposed to be an obstacle to my marriage [to a young heiress in Milan]. My heart… was mutilated by the wound, and I limped along trailing blood. She went back to Africa, vowing to you [God] that she would never know another man… I was wretched, but I couldn’t even manage to emulate a woman.

Cooper may be the first commentator to do justice to this rupture. Her concentration on the Confessions’ women helps her to restore hidden, or half-hidden elements in the drama. For no one could miss the fact that Augustine’s life comes to its defining crisis in Confessions 8, in a walled garden in Milan, where he weeps uncontrollably, and hears a child eerily chanting – ‘Pick it up! Read it! Pick it up! Read it!’ – and finally ‘converts’. And how is he converted? By deciding to never know another woman. It is this decision that marks the purity, and irreversibility, of Augustine’s commitment to God.

Without that scene in Confessions 8, it is hard to imagine the subsequent history of European monasticism – or for that matter, literature or philosophy (no Confessions by Jean-Jacques Rousseau, no Either-Or by Søren Kierkegaard…). Cooper helps us to see that the critical hour in Augustine’s life is not his own. Rather, it is his emulation of the nameless woman he had loved, and then spurned. After all, the original renunciation of ‘the pleasures of the bed’ is not made by him in Confessions 8, but by his devout African lover in Confessions 6. And to be sure, her legacy in Christian and European history is immense.

There are rich chapters in Cooper’s book on Augustine’s too-young fiancée and the formidable late-fourth-century empress Justina. But rather than close with them, it is worth glancing at a passage in Augustine’s City of God against the Pagans, where he contrasts the divine ‘order of nature’ (ordo naturae) and the corrupt libidinal logic of markets (modus aestimationis). By nature, a jewel is inferior to an enslaved girl. But in a Roman market, the girl costs less than a cut stone. Why is this so perverse? Augustine – who opposed slave-trafficking in Roman Africa – tells us, in the early fifth century, that the girl has innate ‘dignity’ (dignitas).

In this new book, Cooper has done more than anyone to draw out the dignity of the women and girls that we can glimpse – and in rare, brief moments listen to – in Augustine’s Confessions.