In 1987 Michael Lapidge argued that a hitherto unedited and anonymous Latin poem on the life and martyrdom of St. Dionysius (Denis, Denys) was in fact an authentic work, long presumed lost, by the famous Hilduin, abbot of Saint-Denis from 814 to 830 and again from 832 to 840.  Preserved only in a late-eleventh-century copy made probably at Winchester (now Oxford, Bodleian Library, MS Bodley 535, fols. 1-38), this metrical Passio S. Dionysii is substantial, consisting of 2,196 hexameters plus several lengthy insertions in prose. In the same article, Lapidge announced his plans to publish the first edition of the poem, but the project grew for reasons well explained in the preface to the almost 900-page volume here under review. Editing the poem demanded a thorough sifting and, in most cases, re-editing of the hagiographic sources behind it. In particular, the metrical passio closely follows Hilduin's own prose Passio S. Dionysii [BHL 2175], for which the standard edition had long been the inadequate sixteenth-century one reprinted by Migne in PL 106, cols. 23-50. Lapidge therefore also undertook to produce the first-ever critical edition of this prose passio by Hilduin, which survives, in various forms, in nearly 200 manuscripts. Hilduin's prose depends, in turn, on two earlier passiones, one of which Lapidge calls "the ancient passio" [BHL 2171] and dates to the later eighth century, the other "the anonymous passio" [BHL 2178], probably of the early ninth century. These (each surviving in about thirty manuscripts) also demanded new critical editions.  Finally, several other texts relevant to Hilduin's activities or to the Carolingian cult of St. Dionysius were also folded into the project, appearing among the present volume's eleven appendices.
What began, then, as an edition and study of a single poem evolved into a monumental presentation of an entire dossier of texts from a crucial period in the growth of St. Dionysius's legend. In addition to making these materials available in scholarly editions with facing translations, Lapidge offers a monograph-length introduction that reassesses the abbot's career and writings. Notable here is the new argument that Hilduin, born perhaps c.785, was a brother of Count Gerold III of Alamannia and thus a nephew to Charlemagne's second wife, Hildegard, and a first cousin to Louis the Pious. Such ties would explain both Hilduin's rise in the Frankish ecclesiastical hierarchy and his lifelong connection to the Alamannic abbey of Reichenau, where, Lapidge speculates, Hilduin might have received his extraordinary education. (Hilduin's immediate predecessor as abbot of Saint-Denis was the former Reichenau abbot, Waldo, who fostered ties between the two great houses.) The troubled reign of Louis the Pious saw Hilduin deposed from the abbacy of Saint-Denis briefly in the early 830s but soon reinstated. In the struggle among Louis's heirs after 840, Hilduin sided with Lothar and lost Saint-Denis as a result, but Lothar compensated him with major honors, including stints as archchancellor, ambassador to Constantinople, and archbishop of Cologne (though it seems Hilduin was never actually consecrated to that see). Hilduin's death year is unknown, but the available evidence places it between 855 and 862.
Any abbot of Saint-Denis would have taken an interest in the patron of his house, but Hilduin's devotion was enflamed by a fateful encounter with the mystical theological writings known as the Corpus Dionysiacum. The original author of these was perhaps a Greek-speaking Syriac Christian of the early sixth century, who posed in his writings as the first-century Athenian philosopher Dionysius "the Areopagite," famously converted by St. Paul in Acts 17:32. A Byzantine embassy of 827 had offered as a gift to Louis the Pious a copy of the Corpus Dionysiacum in Greek, a manuscript that survives today as Paris, Bibliothèque Nationale de France, MS grec. 437. The emperor passed the gift on to Hilduin, with a charge to translate its contents into Latin. Hilduin accepted the assignment, since he had somehow acquired a knowledge of Greek beyond the rudiments. His lack of real fluency, however, combined with the extreme obscurity of Pseudo-Dionysius's original and the careless, lacunose witness afforded by BNF grec. 437, made the task virtually impossible. Quite apart from his many outright errors in translation, he often chose to render Greek terms with bizarre calques or a syntax slavishly close to the original. After usefully surveying some distinctive features of the Latinity in these translations, Lapidge finally admits that they are "at best difficult to understand, at worst simply incomprehensible" (73) without recourse to the original Greek.
However faulty, Hilduin's grasp of the Corpus Dionysiacum would profoundly influence his own contributions to St. Dionysius's legend when, some time after 834, Louis the Pious sent a letter to the abbot charging him to compose a new life of the saint from all available sources. (This is the first of the three letters [BHL 2172-2174] that Lapidge re-edits as Epistolae I-III, with full discussion at 114-1123.) The prose work that Hilduin produced at the emperor's request continued and deepened the spectacular confusions that, by this date (the mid-830s), had already engulfed the historical Dionysius, a martyred early bishop of Paris whom Gregory of Tours had placed in the mid-third century. Lapidge clearly lays out the complicated evolution that ensued (see 81-9), as hagiographers after Gregory pushed this obscure "bishop Dionysius" back in time. First, the so-called ancient passio made him into a first-century missionary to the Gauls, sent by Peter's successor, Pope Clement I. Then, within another generation or two, the "anonymous passio" explicitly identified that St. Dionysius as the Athenian converted by St. Paul in Acts. (The "anonymous passio" is also the earliest source to describe the martyred saint's miraculous carrying of his severed head to the place of his burial.)
For his own passio of the saint, Hilduin took the next step by linking the Corpus Dionysiacum to this supposedly apostolic-age, Athenian-born St. Dionysius of Paris. Indeed, Hilduin so revered the Corpus as itself a kind of holy relic that he devoted several chapters of his new passio to summaries and quotation of its texts. Hilduin's passio also greatly elaborated the narrative of the saint's conversion in Athens according to a source supposedly by a Greek named Aristarchus, who claimed to describe the topography of first-century Athens and offered a vivid report of Paul's encounter with the Areopagite. (Lapidge edits, as Appendix IV, the Latin reliquiae of this fascinating Epistola Aristarchi, which he plausibly speculates  was a Saint-Denis forgery from the early ninth century.) Additionally, Hilduin amplified the descriptions of tortures endured by the martyr and his two companions, Rusticus and Eleutherius, and he also inserted a scene in which Christ appears to the imprisoned Dionysius and serves him communion. Details of this latter episode parallel the account preserved in yet another mysterious source, a short text known as the Conscriptio Visbii [BHL 2183] that Lapidge suggests was also a ninth-century forgery, possibly by Hilduin (see 129 and 762-773 [Appendix VI]).
With all these backgrounds established, Lapidge turns at last to the metrical passio itself, first offering an overview of its sources, language, and versification, then helpfully reviewing and extending his earlier arguments for Hilduin's authorship. In 1987 those arguments had engaged three categories of evidence: (1) the close correspondence generally between the poem and Hilduin's prose passio; (2) the affinities of the poem with other Carolingian verse; and (3) the testimonies of later authorities--namely, Sigebert of Gembloux in the eleventh century, and Aubert le Mire in the seventeenth--that Hilduin had written the legend of St. Dionysius utroque stylo, that is, in prose and verse (le Mire went even further, mentioning that the poetic version was divided into four books, just as the anonymous text in Bodley 535 is). These original arguments were reasonable but not beyond challenge. Lapidge now responds to those who have expressed doubts (see 150-152 and 177-178, n. 91) and bolsters his earlier case with additional, detailed arguments from the syntax, vocabulary, and use of sources common to both Hilduin and the poet (152-157). The evidence, in all, is compelling enough that the burden now surely rests on anyone who would deny the poem to Hilduin.
Both the verse and prose passiones confront an editor-translator with so many problems that readers of this book will find on nearly every page reasons to be grateful that a scholar of Lapidge's vast learning and experience took up the challenge. His editions, translations, and notes will serve researchers well in many areas, whether or not everyone with a stake in the notoriously contested field of "Dionysian" studies will accept all the arguments here made about the dating, sources, and interrelation of items in the dossier. Given the frequent obscurity of Hilduin's style, it is also inevitable that some readers will second-guess how certain passages have been construed, punctuated, or translated, and I have appended to this review a number of possible corrigenda.
But these are, in the grander scheme, eclipsed by the important, long-term contributions of Lapidge's book. Beyond reclaiming and editing a "lost" major work by Hilduin (and thereby also adding a truly extraordinary poem to the corpus of Carolingian verse), this volume has established the first critical edition of Hilduin's influential prose passio. And, if those payoffs were not enough, we are also given new studies and editions of other unusually interesting texts such as the forged Epistola Aristarchi and Conscriptio Visbii. The study of all these materials now stands on far more secure footing, thanks to Michael Lapidge's perseverance.
Queries and possible corrigenda
("HP" = Hilduin's prose passio; "HM" = Hilduin's metrical passio).
58: The phrase potavit...divini nectaris haustus (an analogue from Sedulius Scottus, Carmen 76) may intend to describe Hilduin's poetic activity, as Lapidge argues, but it does not necessarily do so; cf. Ps.-Cyprian, De pascha 23 (Sedulius Scottus's source?) diuini nectaris haustum, where the context is unrelated to poetry.
160 (table): The comparative data about favored patterns of dactyls and spondees, which are said to come from Duckworth's Vergil and Classical Hexameter Poetry, do not seem to agree what the latter actually gives for Paulinus of Nola, Caelius Sedulius, Arator, Cyprianus Gallus, and Dracontius.
165 (line 3): Read "second foot" for "third foot."
222, lines 17-18 (HP cap. 1), qua se manifestauit diuinitate numquam defuisse, quo rediit: Lapidge has "in which [scil. Christ's ascension] He revealed that He had never been absent in divinity--whence He returned" (223); but the sense of quo rediit is "the place to which he returned," as Lapidge rightly takes it when translating the same phrase in the "ancient passio" (641).
222, lines 22-24 (HP cap. 1), Qui siquidem cum imminere suas cernerent passiones quae, Domino Iesu Christo docente, didicerant, repleti spiritus sancti gratia docuerunt: This should mean (if we move the first comma back by one word): "When they [scil. the apostles] saw that their own sufferings were drawing near, being filled with the grace of the Holy Spirit they taught the things that [quae] they had learned as their Lord, Jesus Christ, taught them." But Lapidge translates "When they saw that their own martyrdoms were approaching, which through the teaching of the Lord Jesus Christ they had learned to anticipate," etc. (223), wherein "which" seems to presuppose quas [scil. passiones], not quae as printed. However, quas is the reading adopted for the almost identical sentence in the "ancient passio" (640), and the app. crit. there suggests that quae may well have stood in Hilduin's copy of the source.
222, lines 25-26 (HP cap. 1), qui infestantis inimici iacula probationem fidelium tuorum praestitisti esse et non uulnera: This seems less accurately rendered by the facing translation (223) than by the different one of the equivalent sentence in the "ancient passio" (645).
248, lines 13-21 (HP cap. 10, in a summary of the Pseudo-Dionysian De ecclesiastica hierarchia that draws upon Hilduin's own translation): The long sentence beginning at line 13 could be clarified by placing a full stop in line 17 (changing fas efficitur caelitus operari, maxime etc., to fas efficitur, caelitus operari. Maxime etc.). The relevant part of the trans. would then be "In these [sacraments] he [Pseudo-Dionysius] reveals that all the things that take place through angelic ministry during the most holy and ecclesiastical consecrations of the mysteries operate from heaven above [caelitus operari], through an angelic ministration that accords with each individual order in concert with the ministers of the sacred altar, and especially with the hierarch (that is, the priest), who is rightly made one among the angels. Foremost in the ministry of the holy sacrifice of the Lord's Passion, the most holy principalities..." etc. This same adjustment would also help in the corresponding passage at HM ii.12-21: there delete the period after ii.15 and change commas to periods (or semicolons) after ii.17 and 19, revising the translation as follows: "In these [scil. theoriae] he reveals clearly...that all things which take place in the sacred worship and mysteries of the church...are likewise accomplished [patrari] divinely and from heaven above through the ministry [obsequio] of angelic powers, a ministry that [each] corresponding angelic order rightly claims. Present to those who stand at the altar is a heavenly [caelebs] minister who also, in his role, especially favors [fauens] the hierarch; [the same hierarch], who is rightly and justly made an angel himself, completes the life-giving offerings that are to be miraculously sanctified." Later in the same paragraph, the phrase that Lapidge translates "of the heavenly militia as well as of the supernal power" should modify "holy leaders" (sancti primates at HM ii.26) instead of "altar."
262, lines 13-15 (HP cap. 15), cum audierimus illa, quae non placebant et displicebant benigno Iesu, a discipulis eius, qui fuerunt in carnis commoratione participes mansueti et benigni ipsius spiritus: Lapidge's commentary (494-495, n. 165) justifies the insertion of non (attested in no manuscript) by dismissing the unemended reading quae placebant et displicebant benigno Iesu as "nonsensical" in light of Hilduin's own translation of the relevant source (Pseudo-Dionysius, Ep. VIII.5: Ipsa audientes que non placebant Ihesu). I myself do not find the unemended reading manifestly wrong, if it is translated "since, from those disciples who, for as long as they dwelt in the flesh, were sharers in His gentle and kindly spirit, I have heard what things were pleasing to kindly Jesus, and what things displeasing to Him." This latter interpretation agrees, at any rate, with what the corresponding lines in the metrical version seem to say: nobis cum plura patescant, / quae fuerint placita Iesu, quae foeda, benigno, / magnorum sermone ipsius discipulorum / cuius participes fuerant qui in carne morantes (368, ii.255-258). Lapidge translates this to agree with his emendation in the prose: "since many things are manifest to me which would have been pleasing to kindly Jesus, (but) which (were) unseemly in the speech of His great disciples, who had been His partners while dwelling in the flesh" (369). But the same verses more easily yield "since many things that were pleasing to kindly Jesus, and many that were loathsome to him, are revealed to me by the words of his own great disciples, who were his partners for as long as they remained in the flesh."
262, lines 24-5 (HP cap. 15), illos sibi spiritus benignitate aut malitia sociant, quorum uoluntatem facere inchoant: Lapidge translates "[they] join themselves to Him either in kindliness or malice of spirit, whichever of these two things they undertake to make their intention" (263). I suggest instead "they join to themselves, by their kindness or wickedness, those [angelic] spirits whose will they are beginning to carry out." For the corresponding verses on 368 (HM ii.280-281, hos sibi consociant sanctos reprobos quoque flatus, / quorum se uotis potius concurrere censent," I would accordingly substitute for the translation provided on 369 something like "they join to themselves holy [angelic] spirits as well as damned ones, as they perceive themselves in accord with the aspirations of the one or the other." 
290, lines 13-14 (HP cap. 30): Move the comma to after pagana (taken as nom. sg.), yielding "Larcia was there, who, although still a pagan, was nevertheless moved by curiosity concerning miracles."
296, lines 20-5 (HP cap. 33), sed Deus omnipotens, praescius futurorum--qui mutat tempus...iniquorum consilia suae dispositionis arti industria qua uoluit seruire coegit: Lapidge translates, "but God almighty, mindful of future events--He who alters time...constrained the intentions of the wicked to the design of His intention through the application by which He wished to be of assistance" (297); for the latter part of this, I would suggest "[God] purposefully, in the manner he willed, forced the plans of the wicked to serve the design of His providence." For the first part of the sentence, the commentary might identify the echo of Dan. 2:21.
308: The opening lines of the poem (HM i.1-10) form an extremely long period of hopeless syntax, for which the facing translation (309) construes the main subject as "that great day [Pentecost]"; but the preceding lines make more sense if "Christ" or "the cross" is understood as the subject, the latter interpretation (cross) finding added support in a subsequent reference (HM i.115-16) and, ultimately, in an often imitated metaphor of Sedulius, Carmen paschale v.188-195.
312 (HM i.89-90): Describing Athens, the poem says, Vbera materna seu uiscera dicta paterna / eloquiis foueat matrum quod amore clientes: Lapidge translates "Called 'the mother's breasts' or 'the father's innards,' let it cherish in the speech of its mothers what its allies (cherish) in its behaviour" (313). Since causal quod is not rare in the poem, however, the latter part of this (from "let it cherish...") makes better sense as "because, in motherly love, [the city] nurtures its dependents with eloquence" (note also, a few lines later in Hilduin's prose, the phrase fandi et eloquentiae nutrix, with a parallel at HM i.96).
318 (HM i.190): The sun's acies are more easily understood as "(pointed) beams, radiance" (cf. Vergil, Georgics i.395) than "battle lines" (as on 319).
340 (HM i.588-590), is uelut in caelo posuit qui mentis hiatum, / caelica dum reserans aeterna cubilia lustrat, / corde quibus mundo iam Christo dante manebat: Lapidge translates, "just as He, Who established in heaven the high-flown mental style, revealing heavenly mysteries while He traverses His eternal dwelling place, remained in those of pure heart through Christ's beneficence" (341). But this rendering seems to have lost sight of the corresponding prose (244/5, HP cap. 9) with its clarifying allusion to Ps. 72:9 posuerunt in caelum os suum (duly noted in Lapidge's commentary on the prose, at 483, n. 71). The intended sense of the metrical version is thus probably "just as he [the Psalmist?] did, who set the mouth [hiatum] of his mind in heaven, as he explored and opened heaven's eternal chambers, in which he was already dwelling by virtue of his pure heart, as Christ bestowed." 
358/60 (HM ii.151-154), uir Deus ast factus, celso de cardine missus, / ciuibus ut notis quendam pietate uirilem: / effectum Domini mira nouitate refertum / donauit mitis Phoebi sub lampade nobis: Lapidge translates, "but (rather) as God-made-man, sent from the heavenly summit, so that He (should perform) a particular human act through mercy for the known citizens (of the world): he gave to us an event, replete with the marvellous novelty of the Lord, under the lamp of gentle Phoebus" (357/9). The passage is telling since, as Lapidge's introduction argues (157), it seems improbable that any poet other than Hilduin himself could have divined the meaning of the opaque neologism perciuilitare and other obscurities in prose source, namely HP cap. 13 (256, lines 4-5): sed uir Deus factus, nouam quandam Deiuirilem operationem nobis perciuilitauit, which Lapidge translates, "but as God-made-man, He accomplished for us a new kind of divine-manlike activity" (257). This argument is persuasive (and might also stress the poem's ciuibus ut notis as a further reflex of perciuilitauit); and yet the punctuation and translation of the verse at this point obscure rather than highlight its closeness to the prose. Deleting the colon after HM ii.152 and inserting commas after Domini and refertum in line 153 will yield something nearer to the prose: "but rather as one who became a God-man, sent from a high summit to bestow mercifully a certain man-related operation of the Lord (uirilem effectum Domini = Deiuirilem operationem in the prose), an operation fully wondrous and unprecedented, upon us as his fellow citizens here beneath the lamp of gentle Phoebus [i.e., here on earth]."
358 (HM ii.163-164): Change the period after 163 to a comma and translate as a single sentence, "Indeed he says that the utterly profound darkness of God is light inaccessible to all those who" etc. (cf. the prose on 256, lines 6-7).
360 (HM ii.201): Lapidge has probably chosen the safest course here by obelizing the clausula in scribens de [MS in] †sole stupore for reasons set out in the commentary (558-589). But then again, I note that Hilduin's translations of Pseudo-Dionysius include such forms as solenatas, soliuis(a)e, and soliuolut(a)e--all calques on Greek compounds with helios as their first constituent. So a neologism *solestupor "a wonder of (or at) the sun" cannot actually be ruled out, even though I know of no actual Greek word that such a form would translate.
366 (HM ii.235), uis ualde uerendam: Perhaps read uim, as the translation implies.
368 (HM ii.271-272): Delete the semicolon after 271 and translate the two lines as "He accuses no one, nor does he rebuke for past sin those who have been admitted to the sacred delights of His table."
370 (HM ii.390): Delete the semicolon and translate the whole line "especially since I speak truth and do not pursue vanities."
442 (HM iv.676): The phrase non ficto scemate cautus is opaque, but an alternative to Lapidge's rendering (443 "being guided by a model that is not fictional") might be "not hesitantly, with feigned rhetoric"--therefore perhaps a jab at the author of the "anonymous passio" who, at the end of his own work (see 702, lines 3-8), thickly applies the modesty topos. The sentiment of non ficto scemate, taken this way, would be wholly consistent with Lapidge's characterization of Hilduin's harshness towards the "anonymous passio" and its author (see 666-7).
446 (HM iv.725), ad nostrum deducta [scil. passio] stilum multumque liquata: In the commentary perhaps note the parallel in Ep. II, cap. 2, Hilduin's letter to Louis (see 202, lines 28-29: haec, quae ab aliena lingua expressimus, in tenoris serie, sicut de praelo sunt eliquata, texemus), since the metaphor of the wine press as authorship--specifically the idea of extracting new matter out of source texts--is a relatively distinctive one and so might join other arguments connecting Hilduin to the poem.
491, n. 139 (comment to HP cap.14): The reference "II Sm xx. 8-12" should be II Kings (IV Kings) 20: 8-11 (as correctly on 559).
639, n. 101: Might the unidentifiable "quotation" in the preface to the "ancient passio" (at 638, lines 11-13: Et ut habet testimonium ueritatis, "plus fidelium sunt relatione comperta, quam probentur ad nos lectione transmissa" ) simply be a paraphrased recollection of John 21:25?
766, line 16 (in the Conscriptio Visbii): In a ninth-century setting, the author's idiom here celebrare dominicas for "celebrate mass" (cf. HP cap. 29, at 290, lines 2-4: Dominica missarum solemnia...celebraret) has a whiff of archaism. 
Sometimes, when the translation justifiably converts Hilduin's long poetic periods into two or more Modern English sentences, that punctuation seems to have been transposed back onto the Latin, where it does not suit the grammar of the source text: e.g., HM i.260-265 (and I would incline to move the final stop to the end of 266); ii.388-394; iii.54-63, 63-64, and 145-151; iv.617-622.
1. "The Lost Passio metrica S. Dionysii by Hilduin of Saint-Denis," Mittellateinisches Jahrbuch 22 (1987), 56-79.
2. Lapidge published the editions of these two source-texts previously as "The 'ancient passio' of St Dionysius (BHL 2171)," Analecta Bollandiana 132 (2014), 241-285; and "The 'anonymous Passio S. Dionysii' (BHL 2178)," Analecta Bollandiana 134 (2016), 20-65. For another recent overview of the relation of these texts to Hilduin's dossier, see Nikolaus Staubach, "Fälschung--Fiktion--Prophetie: Die Areopagitica Hilduins von St. Denis," in Prophetie und Autorschaft: Charisma, Heilsversprechen und Gefährdung, ed. Christel Meier and Martina Wagner-Egelhaaf (Berlin, 2014), 105-28.
3. Both these revised translations also bring Hilduin's meaning closer to his Pseudo-Dionysian source in these passages, namely Ep.VIII.5 (to Demophilus).
4. The expression os mentisis patristic; e.g., Augustine, De Genesi ad litteram 12.26.54; Cassiodorus, Expositio in psalmos 118.131.
5. See Ludwig Eisenhofer, Handbuch der katholischen Liturgik, 2 vols. (Freiburg im Breisgau, 1932-33), I, 3-4.