At his untimely death in 2020, the late and much lamented Richard Sharpe left not only a published legacy dwarfing that of most his contemporaries, but an unpublished Nachlass of daunting magnitude. Thanks to David Crouch and his rescue party, some at least of this rich seam is now exposed to view. More will follow, not least from two major research projects (Gerald of Wales, and Rufus/Henry i) for which Sharpe's admirers have secured ongoing support. Meanwhile, here we have a definitive study of the earliest materials for one of England's greatest, yet until now somewhat neglected Benedictine houses: the abbey of St Mary at York. This focus is all the more appropriate as Sharpe himself grew up and was schooled in the abbey's curtilage. As Michael Gullick explains, our principal source is a manuscript acquired by the British Library in 1914 (ms Add. 38816): a late sixteenth-century collection of scraps, preserving twelfth-century copies of three forged or heavily interpolated royal charters (of Rufus, Henry i and Henry ii) together with a foundation history attributed to St Mary's first abbot, and a confraternity list. For the foundation itself there seem to have been three chief movers: Abbot Stephen, originally a monk at Whitby, Count Alan of Brittany and King William i. To these we might add the Venerable Bede, who died more than three centuries before Abbot Stephen, yet who supplied an account of northern monastic revival crucial to what occurred after 1066 not only at York, but at Whitby and Lastingham: locations via which the community of St Mary's migrated before coming to rest in its permanent site, north-west of York's city walls. What exactly went wrong at Whitby: internal bickering, hostile interference from lay patrons or fear of sea-borne attack? Why did Stephen's community then move from Lastingham to York: local piety, penance for the Conqueror's ‘Harrying of the North’ or deliberate royal usurpation of a site uncomfortably associated with the suppressed earldom of Northumbria? In what precise circumstance was the abbey's endowment acquired and augmented? All of these remain questions lacking any sure answer. Even so, in a bravura exercise in stratigraphy, Sharpe himself identifies the two hundred or so individual grants listed in the three royal charters of inspeximus, in seventy-four cases tracing them to surviving charters, here edited from cartulary and other copies. As was his way, Sharpe's approach involves breaking down the bigger picture into a series of individual pixels. The use of forgeries here, to access truths, is uniquely accomplished, indeed little short of miraculous. Places and persons are for the first time fully identified (greatly improving upon Farrer's Early Yorkshire charters). In the process, light is shed not only on the disparity between charters and foundation history, but on the circumstances in which Domesday Book records details in 1086 still in a state of flux. Nicholas Karn's edition and translation of Abbot Stephen's narrative, like Janet Burton's of the confraternity list, are likewise immensely useful. Even so, questions remain. The most pressing concern the circumstances and motivation for forgery at St Mary's. When were the royal charters first concocted or interpolated? What was so lacking in whatever title deeds the abbey possessed as to induce the monks to ‘improve’ or ‘reinvent’ so many of their early documents? And when did this programme end: in the twelfth century, or long afterwards? Here, the survival of a long but distinctly peculiar confirmation in the name of Richard i, first recorded in 1308, and the fact that in 1257 a spurious writ of Henry i was for the first time presented for royal confirmation, suggest an extended programme of forgery, long after the 1150s. Into the 1350s, the confirmation by Henry ii was still being revised and ‘improved’. As late as 1405, indeed, not noticed here, we find St Mary's turning up at the royal Exchequer with what were claimed to be eleventh-century evidences, including one (a charter of Rumfrey of Lincoln, first recited in the Memoranda Roll for the year 6 Henry IV) that greatly extends our knowledge of a transaction known to Sharpe only from its summary in the forged confirmation charter of Henry i (p. 154 no. 58).Footnote ¹ If we turn to Janet Burton's confraternity list, and adopt a similarly stratigraphic approach, once again assuming that position indicates date, either earlier or later, then by the reign of Henry i St Mary's already considered itself part of an unofficial congregation uniting York, Evesham, Whitby and Colchester. Since all four houses were amongst England's more notorious entrepôts of forgery, how might this affect our wider understanding? Indeed, now that the individual pixels are listed, how should our larger picture be retouched, reassessed or rehung? Here, on the macro rather than the micro scale, clearer guidance may one day emerge. Nor is everything entirely as Sharpe might have wished it to be, even in pixelated miniature. Translations are useful but not always perfect: i.e. pp. 390–1 line 4 (where a comma missing between ‘erat’ and ‘monachus’ allows the monk rather than the place to be identified, as ‘under the sole power of the King’), pp. 396–7 final lines (where the king is misleadingly described as sealing his own charter) or pp. 406–7 line 2 (where ‘divine religion’ should not be described as ‘great’, but we are referred ‘especially’ [‘maxime’] to the light such religion casts). ‘Linleii’ (pp. 414, 420–1) is more likely Benedictine Lonlay (Orne, cant. Domfront) than Sempringhamite Bullington. And what pleasure Sharpe would have derived from a philological muddle over the word ‘werpire’ (pp. 400–1), here clearly, as in Ducange's ‘guerpire’, ‘to release or set aside’. Linguist, list-maker, historian, Sharpe was uniquely well-qualified. We may never see his like again. In the meantime, we should be grateful to Crouch and his team for making so good and useful a book from what might otherwise have been a mere ‘if only’.