A 10th-century cryptic political-moral satire censuring the corruption and ambition of Italian princes and clergy, written in deliberately obscure Latin to disguise its targets. This second recension is Atto of Vercelli's own slightly clearer rewrite of his original Polypticum, offering insight into Ottonian-era political invective and the medieval Latin tradition of esoteric writing.

Historical Context

Authorship: The Polypticum quod appellatur Perpendiculum is traditionally attributed to Atto, Bishop of Vercelli (924–961), though earlier scholarship debated this. In 1832 Cardinal Mai first published the Polypticum (Perpendiculum) as Atto’s work (www.catholicity.com). A 19th-century historian, Adolf Ebert, argued the treatise might be by a Spanish author, casting doubt on Atto’s authorship (www.catholicity.com). However, prominent scholars like A. Hauck defended Atto’s authorship as the “traditional view” (www.catholicity.com). Modern research strongly favors Atto’s authorship: internal evidence (allusions to contemporary events and persons) and the survival of the text in a codex of Atto’s works support his hand (www.degruyterbrill.com) (www.degruyterbrill.com). Today, the Polypticum/Perpendiculum is included in critical editions of Atto’s works (www.degruyterbrill.com) (www.degruyterbrill.com), and scholars treat it as an authentic work of Atto of Vercelli.

Date of Composition: The treatise was composed in the mid-10th century, likely between 953 and 960 (cris.unibo.it) (cris.unibo.it). Atto appears to have written it in the final years of his life (he died in 961) (www.degruyterbrill.com). The text itself alludes to the tumultuous politics of Italy up to the mid-950s, including the reign of King Berengar II (r. 950–961) and the looming intervention of King Otto I of Germany (www.degruyterbrill.com) (www.degruyterbrill.com). These references anchor the date to the late 950s, just before Otto’s invasion of Italy (961). Atto likely finished the work by c.957–960, as he warns of an impending usurpation – fulfilled when Otto I moved against Berengar II (cris.unibo.it) (www.degruyterbrill.com).

Provenance: The Polypticum was written in northern Italy, almost certainly at Vercelli, where Atto was bishop. Atto had been a Lombard noble (he proudly “lived by Lombard law” (www.treccani.it)) and became bishop of Vercelli in 924 after a Hungarian raid killed his predecessor (www.encyclopedia.com). As bishop, he served as royal chancellor to Kings Hugh of Provence and Lothair II of Italy (www.encyclopedia.com), and was deeply involved in court politics. The treatise’s immediate context was the power struggle in Italy after the Carolingian collapse – multiple “usurpers” contended for the Italian throne (cris.unibo.it). Atto wrote under circumstances of political chaos: Berengar II had seized Italy’s crown (950) and faced opposition from nobles who invited Otto’s intervention. The Polypticum was likely penned as a private admonitory letter or teaching text in the Vercelli cathedral school (www.degruyterbrill.com) (www.degruyterbrill.com), amid Atto’s efforts to guide both his clergy and fellow bishops during this crisis.

The Cathedral of Vercelli, where Atto served as bishop from 924-961 and likely composed the Polypticum for use in his cathedral school
License: * CC BY-SA 3.0 (Photo by Luca Volpi

Historical Setting: Mid-10th-century Italy was in turmoil. Politically, the Kingdom of Italy (northern Italy) was wracked by successive usurpations after the death of the last Carolingian emperor in 888 (www.degruyterbrill.com). Kings Hugh of Arles (r. 926–947) and then Berengar II (r. 950–961) struggled for legitimacy. Berengar II and his son Adalbert were viewed by some as tyrannical, and their rule prompted appeals to Otto I of Germany to intervene (www.degruyterbrill.com). Religiously, the mid-900s preceded the Gregorian Reform; church leaders like Atto navigated a world of lax morality and secular encroachment. Culturally, it was the age of the “iron century” – a perceived dark period – yet Atto’s court connections and scholarship show that intellectual activity persisted in Italy (www.encyclopedia.com). Atto himself was a learned theologian with knowledge of Greek and Latin Fathers (www.encyclopedia.com), attempting to uphold ecclesiastical order during civil instability. The Polypticum speaks to that moment: Atto condemns the “crimes of the powerful” and the cycle of coups in post-Carolingian Europe (cris.unibo.it) (www.degruyterbrill.com), all in light of divine judgment.

Political divisions in Italy around 1000 AD, showing the fragmented landscape that Atto witnessed during his episcopal career under multiple competing rulers
License: * CC BY-SA 3.0 (Map by “MapMaster”

Intended Audience: Externally, the work takes the form of an open letter or epistle, addressed cryptically to a “Reverend Fulano – a most eminent prelate” (Fulano being a placeholder name) (la.wikisource.org). Modern scholars deduce that the likely real addressee was Ratherius (Raterio) of Verona, a fellow bishop (www.degruyterbrill.com) (www.degruyterbrill.com). Ratherius was known for his outspoken views and may have favored Otto’s intervention; Atto seemingly writes to dissuade him and others from supporting usurpation (www.degruyterbrill.com) (www.degruyterbrill.com). In this sense, the Polypticum was a didactic exhortation to Atto’s episcopal colleagues, urging them to remain loyal to lawful (if flawed) kings and resist the temptation of foreign saviors. At the same time, Atto prepared a second, simplified version with extensive glosses for use in his own diocese’s cathedral school (www.degruyterbrill.com) (www.degruyterbrill.com). Thus the original audience was twofold: clerical intellectuals (like Ratherius) for the sophisticated political message, and Atto’s students and clergy for the moral and educational content. The work was written “under the guise of a letter” to deliver a prophetic warning to Italy’s elite (cris.unibo.it), while doubling as a pedagogical tool “to educate his clergy” and shape their Latin learning (www.degruyterbrill.com) (www.degruyterbrill.com).

Theological Significance

Core Themes: The Polypticum is a fierce moral and political critique couched in theology. At its heart, Atto decries the vice of ambition and unlawful usurpation of power (cris.unibo.it) (www.degruyterbrill.com). He portrays the lust for power as a spiritual disease: one that seduces rulers, “serpentine” in its growth and ultimately destructive (la.wikisource.org). The central argument is that even wicked rulers are permitted by God’s will, and usurping a lawful king is a grave evil. This reflects Romans 13:1–2 (“there is no authority except from God”) and invokes the biblical principle of not harming the Lord’s anointed. Atto warns that the continuing cycle of coups in Italy will bring divine judgment and social ruin (www.degruyterbrill.com) (www.degruyterbrill.com). Woven into this is a pastoral plea for repentance: the powerful must answer for their crimes before God. The text is also a “mirror for princes” in satirical form – it lists the corruptions of worldly leaders (pride, oppression, betrayal) to urge reform (cris.unibo.it) (www.degruyterbrill.com). Through allegory and paradox, Atto emphasizes humility and legitimacy as the only stable foundation for governance.

Patristic Context: Intellectually, Atto stands in the tradition of the Latin Church Fathers while writing in a post-patristic era. He was familiar with Augustine, Jerome, and Ambrose, citing Scripture frequently and adhering to orthodox doctrine. Like Saint Augustine’s City of God, Atto’s work contrasts earthly turmoil with divine justice – implicitly reminding readers that God ordains rulers and will judge them (www.degruyterbrill.com) (www.degruyterbrill.com). Atto’s style, however, is closer to late Latin writers such as Martianus Capella or Aldhelm, who employed complex vocabularies – a trend known as hermeneutic Latin. Indeed, the Polypticum’s Latinity is notoriously “mysterious and enigmatic”, full of rare words and rhetorical figures (www.catholicity.com) (www.degruyterbrill.com). This recalls the classical satirists (like Juvenal) in its allusive invective (cris.unibo.it) (www.degruyterbrill.com), and also mirrors the hermeneutic style found in 10th-century Anglo-Latin scholars. Atto was likely tapping into the same revival of complex Latin seen in his contemporaries. Moreover, as a bishop, he echoes St. Gregory the Great’s pastoral voice – Gregory too admonished secular leaders (e.g. Emperor Maurice or local rulers) albeit less cryptically. Atto’s insistence on lawful authority also resonates with Pope Gelasius I’s two-powers theory (distinguishing spiritual and temporal spheres); Atto, however, focuses on internal usurpation within the temporal sphere.

Biblical Foundation: Scripture undergirds the Polypticum throughout. Atto interprets contemporary events through an eschatological lens, drawing on biblical imagery of judgment. Notably, the title “Perpendiculum” (plumb-line) comes from Isaiah 34:11, where God “stretches over [Edom] the measuring line of chaos and the plumb-line of desolation” (www.biblegateway.com). Atto invokes this prophecy to suggest that God’s plumb-line of judgment is poised over Italy’s sinful rulers (www.degruyterbrill.com). He implies that just as God measured Israel with a plumb-line (cf. Amos 7:7-8), He will measure Italian kings for their transgressions. The work also alludes to biblical exempla: for instance, the “labyrinth” metaphor in the letter’s preface evokes the idea of losing one’s way morally (la.wikisource.org), echoing biblical warnings about the path of the wicked. Although Atto avoids naming individuals, he likely had Biblical archetypes in mind – e.g. rebellious Absalom or King Saul’s tragic end – to subtly parallel Berengar’s situation. He certainly cites or paraphrases the Wisdom literature on pride and downfall (e.g. “pride goeth before destruction”). The many interlinear glosses in the simpler version even include scriptural explanations (www.degruyterbrill.com) (www.degruyterbrill.com). Thus, the Polypticum is thoroughly biblical: it applies prophecy and wisdom teachings to 10th-century politics, urging rulers and bishops to heed God’s word rather than worldly counsel.

Controversies: While doctrinally orthodox, the Polypticum did engage in live political-theological debates. One implicit controversy was over the role of the German king (Otto I) in Italy. Atto takes a stand against those Italian bishops who welcomed Otto’s intervention, asserting that Berengar II, however flawed, was the legitimate king by God’s allowance (www.degruyterbrill.com) (www.degruyterbrill.com). This put him at odds with pro-Ottonian churchmen like Liutprand of Cremona, who harshly criticized Berengar and celebrated Otto (www.degruyterbrill.com). In essence, Atto’s treatise contributed to a controversy on legitimacy vs. tyranny: is it righteous to topple a sinful monarch? Atto’s answer, rooted in Augustinian thought, was essentially conservative – usurpation is an evil worse than a bad king, because it breeds chaos and invites divine wrath (www.degruyterbrill.com). This stance may have been contentious among reform-minded clergy who saw Otto as a savior. Additionally, Atto’s obscure writing style itself drew criticism or puzzlement. Later readers found it so impenetrable that some doubted an Italian bishop could compose it (hence Ebert’s speculation of Spanish origin) (www.catholicity.com). The enigmatic prose was therefore a kind of intellectual controversy: it was a deliberate challenge to the reader, perhaps to discourage casual or hostile readers from easily comprehending its political barbs. There is no indication Atto was accused of heresy – his theology is sound – but his frank admonitions could well have rankled powerful figures of his day.

Influence: The Polypticum’s immediate impact was likely limited to learned circles, but its significance has grown in hindsight. In Atto’s own milieu, the text would have bolstered the argument for political patience and spiritual reform from within, rather than relying on foreign intervention. It thus provides a rare Italian counterpoint to the dominant narrative written by Liutprand (who celebrated Otto’s takeover). Modern historians value Atto’s work as a unique narrative source on 10th-century Italy (www.degruyterbrill.com) (www.degruyterbrill.com). Because Liutprand’s Antapodosis long stood as the only account of that era, the Polypticum (once decoded) “adds significantly to our knowledge of the Italian kingdom” (cris.unibo.it), revealing an indigenous critique of the political situation. In terms of intellectual history, Atto’s use of classical rhetorical structure and satirical satire prefigures later medieval styles of moral satire (one can see echoes, for example, in the 12th-century Polycraticus of John of Salisbury, which similarly condemns court vices albeit in clearer Latin). The educational version of Atto’s text, with its 3,000 interlinear glosses, indicates influence on pedagogy: it became a tool to teach the liberal arts (grammar, rhetoric) to young clerics without exposing them to pagan texts (www.degruyterbrill.com) (www.degruyterbrill.com). In this, Atto anticipated the High Middle Ages’ trend of creating Christian Latin classics for study. Finally, Atto’s emphasis on the accountability of rulers under God’s law feeds into the broader Christian political theory that burgeoned in the Gregorian Reform and beyond. While his work was not widely copied, its rediscovery has cemented Atto’s legacy as one of the foremost Italian ecclesiastical writers of the 10th century (www.treccani.it), shaping modern understanding of the era’s theology and politics.

Manuscript Tradition and Editions

Manuscripts: The Polypticum survives in very limited manuscript witnesses, suggesting it was not widely disseminated. The principal manuscript is Vatican Library, MS Vat. lat. 4322, a 10th-century codex likely copied under Atto’s direct supervision at Vercelli (www.wiglaf.org). This manuscript is essentially Atto’s compiled works and includes the Polypticum. It remained in Vercelli’s cathedral library for centuries before the Vatican acquired it in the 17th century (promptly making a copy, now MS Vat. lat. 4323) (www.wiglaf.org) (www.wiglaf.org). Vat. lat. 4322 contains both known versions of the text: the complex original redaction (A) and the simplified redaction (B) with extensive glosses (www.degruyterbrill.com) (www.degruyterbrill.com). In the manuscript, the Polypticum is introduced as an epistle (with a pseudonymous greeting) followed by an argumentum and then the main text (la.wikisource.org) (la.wikisource.org). The second “textus alter” (alternate text) appears as a clarified rewrite with interlinear and marginal notes explaining the obscure vocabulary (www.degruyterbrill.com). Because of the manuscript’s unique format, earlier cataloguers were unsure if the work was truly Atto’s – the Migne Patrologia Latina entry even listed it as “Auctor incertus (Atto Vercellensis?)” (la.wikisource.org). Aside from the Vatican codex, no other medieval copies are firmly known. It’s possible that Ratherius of Verona had a copy (if he was the recipient), but if so it has not survived or been identified. Essentially, the Polypticum’s preservation rests on the single Vercelli/Vatican lineage.

Critical Editions: The first printed edition of the Polypticum was by Cardinal Angelo Mai (1832), who uncovered it in Vatican manuscripts and published it with Atto’s sermons (www.catholicity.com). J.-P. Migne then incorporated Mai’s text into Patrologia Latina vol. 134 (Paris, 1853) – where it appears in two forms, corresponding to the two recensions (columns 859–880 and 881–894) (www.documentacatholicaomnia.eu) (www.documentacatholicaomnia.eu). The Migne text, based on Mai, was adequate for its time but lacked modern critical rigor. A significant scholarly edition came in 1922, when Georg Goetz produced a critical text (Abhandlungen der Sächsischen Akademie, vol. 37.2) (www.encyclopedia.com). Goetz’s edition improved the reading of the difficult Latin but still left many obscurities. The definitive edition is very recent: Giacomo Vignodelli’s 2019 critical edition (Ed. Nazionale Testi Mediolatini d’Italia, vol. 54) (www.degruyterbrill.com) (www.degruyterbrill.com). Vignodelli’s edition is based on a painstaking collation of the Vatican manuscript and includes both Redaction A and B plus all glosses, presented in parallel for the reader (www.degruyterbrill.com). It clears up numerous textual cruxes and provides a full commentary. This 2019 edition also comes with an Italian translation (traduzione) and commentary, making the work far more accessible (www.degruyterbrill.com) (www.degruyterbrill.com). There is no published English translation to date, and any English discussion (e.g. Vignodelli’s 2016 article) has only summarized or excerpted the Latin. Scholars needing the text rely on Vignodelli 2019 or Goetz 1922, as the Migne version contains some inaccuracies and outdated conjectures.

Existing Translations: As noted, Italian is currently the only modern language with a complete translation, included alongside the Latin in Vignodelli’s edition (www.degruyterbrill.com). No full English or French translation is in print, though analyses exist in those languages. Portions of the text have been paraphrased in scholarly articles in English (cris.unibo.it) (cris.unibo.it). The Catholic Encyclopedia (1913) characterizes the Polypticum as “an abridgment of moral philosophy, written in a mysterious and enigmatic way” (www.catholicity.com), but that is a description rather than a translation. It’s worth noting that Atto’s interlinear glosses sometimes translate his own rare Latin words into simpler Latin; in effect, Atto himself provided a kind of translation for students within Redaction B (www.degruyterbrill.com). Those glosses can aid modern readers in understanding the text’s meaning. For a broader audience, however, the work awaits a dedicated English translation.

Textual Issues: The Polypticum poses special textual challenges. First, it exists in two recensions: Redaction A is a virtuoso piece of convoluted prose, while Redaction B is a pruned and reworded version for clarity (www.degruyterbrill.com). Atto likely composed A first, then himself (or under his direction) produced B with explanatory glosses (Glossa C) (www.degruyterbrill.com). This self-glossing is unusual and required Vignodelli’s edition to print both versions side by side. Secondly, the language is deliberately archaic and rarefied (“obscuritas lessicale et stilistica”) (www.degruyterbrill.com). Scribes who copied it – if any beyond the original – may have introduced errors by misunderstanding uncommon words. The sole surviving manuscript shows a few places where later correctors added clarifications, indicating that even medieval readers struggled. For example, Atto uses the word “cantabries” (an obscure term) and then glosses it himself as “ut pollini” (“like chaff”) (la.wikisource.org). The critical apparatus notes many such unusual terms and how the glosses interpret them (www.degruyterbrill.com). Another textual issue is the identity of the pseudonymous names. The preface addresses “Fulano” (Latin for “so-and-so”) (la.wikisource.org), and the speaker in the preface is also called “Fulanus.” This was not a scribe’s omission but Atto’s intentional anonymity, perhaps to protect the real correspondent. Early editors were unsure if “Fulano” concealed a real figure. Modern scholars propose Ratherius of Verona as the likely referent (www.degruyterbrill.com). Lastly, minor variants can be found between the two known printed sources: one version of the text came from a collection by Jean Baluze, and another from a collection of older writers (www.documentacatholicaomnia.eu). Migne printed both as “Polypticum” and “Polypticum (textus alter)” to capture these versions (la.wikisource.org) (www.documentacatholicaomnia.eu). Vignodelli has shown these are not truly independent traditions but the two recensions from the same manuscript line. In sum, thanks to the fresh critical edition, the textual state is now much improved: the complex puzzle of Atto’s Latin has been solved to a great extent, confirming the integrity of the work and revealing Atto’s didactic genius in providing his own “key” to the labyrinth.

Author Biography

Life: Atto of Vercelli (c.885 – 961) – sometimes called Atto II to distinguish him from an 8th-century namesake – was a Lombard nobleman who became one of 10th-century Italy’s leading churchmen (www.encyclopedia.com). He was born around 885 into a distinguished family (by one account the son of a Viscount, Aldegarius) (www.catholicity.com). Atto himself claimed Lombard heritage proudly, stating he lived by Lombard law (www.treccani.it). He likely received an excellent education – possibly outside Italy, in the Frankish realms – as his later writings show mastery of Scripture, canon law, and even some Greek (www.encyclopedia.com). The turning point of Atto’s career came in March 924, when Magyar (Hungarian) raiders devastated northern Italy. During an attack on Pavia, the Bishop of Vercelli, Regembert, was killed, and Atto was chosen as his successor as Bishop of Vercelli (www.encyclopedia.com). He would lead the Diocese of Vercelli from 924 until his death on December 31, 961 (www.encyclopedia.com).

As bishop, Atto quickly rose to prominence in both ecclesiastical and secular spheres. He became a trusted advisor to King Hugh of Provence, who was then King of Italy. By 933 Atto was appointed Grand Chancellor to King Hugh (effectively the highest administrative officer) (www.catholicity.com). He continued in this influential role under Hugh’s son and co-ruler Lothair II (King of Italy until 950) (www.encyclopedia.com). Through these positions, Atto secured royal grants and privileges for the Church of Vercelli (www.catholicity.com) – one chronicler notes Hugh’s gratitude resulted in donations enhancing Vercelli’s holdings (www.catholicity.com). After Lothair II’s untimely death in 950, power in Italy shifted to Margrave Berengar II of Ivrea, who crowned himself king. Atto maintained a relationship with Berengar II (d. 966) as well (www.encyclopedia.com), though likely more strained: Berengar was often at odds with some bishops. It is in this late period that Atto wrote his major works, addressing the challenges of church and state.

Career and Works: Atto’s episcopal career combined active governance with scholarly output. He was a reformer at heart, concerned with ecclesiastical discipline and education. Around 940, he composed his earliest major work, De pressuris ecclesiasticis (“On the Oppressions of the Church”) in three books (www.encyclopedia.com). This treatise tackled pressing issues: it defended the clergy against unjust accusations, discussed proper procedures for filling bishoprics, and decried the seizure of church property by lay magnates upon a bishop’s death (www.encyclopedia.com). This text sheds light on abuses Atto witnessed – e.g. nobles confiscating a deceased bishop’s lands – and argues for the Church’s rights in such matters. He also compiled the Canones statutaque Vercellensis ecclesiae, a collection of diocesan statutes and canons. (www.encyclopedia.com) Notably, Atto incorporated material from the False Decretals of Pseudo-Isidore in these canons (www.catholicity.com), indicating he had access to that influential (if forged) corpus of church law – showing his interest in bolstering episcopal authority through legal tradition (www.catholicity.com). Another scholarly endeavor was his Commentary on the Epistles of St. Paul (www.encyclopedia.com). He wrote a lengthy exegesis of the Pauline letters, even addressing curiosities like why the Epistle to the Romans comes first (www.encyclopedia.com). This commentary reflects Atto’s solid grounding in patristic theology and his didactic aim to explain Scripture to his clergy.

In addition, 18 of Atto’s Sermons survive (published by Cardinal Mai) (www.catholicity.com), which give insight into his preaching style and pastoral concerns. His sermons for Lent and feasts emphasize moral renewal and often quote Church Fathers, aligning him with the Carolingian homiletic tradition. Throughout his career, Atto remained engaged in church councils and politics. In the 940s–950s, he was involved in synods addressing church discipline in Italy. He also corresponded with notable contemporaries; several Epistolae (letters) of Atto are preserved (www.catholicity.com) (www.encyclopedia.com), dealing with doctrinal questions and practical church matters. One letter, for instance, responds to accusations against clerical marriage, defending Western discipline – illustrating Atto’s role as a mediator in controversy (www.encyclopedia.com).

Atto’s final years were dominated by the turmoil of Berengar II’s reign and Otto I’s intervention. While many Italian nobles turned to Otto the Great, Atto, as evidenced in his Polypticum, counseled loyalty to the established (if imperfect) king (www.degruyterbrill.com) (www.degruyterbrill.com). This put him somewhat at odds with the pro-Otto faction. Nevertheless, when Otto I invaded in 961, Atto was elderly; he died at the end of that year, just as Otto was crowned Emperor. Atto was buried in Vercelli (tradition holds in the Cathedral of St. Eusebius). Although never canonized, he was esteemed locally – a 1920s biographer called him “the greatest Italian bishop and writer of the 10th century” (www.treccani.it).

10th-century ivory plaque depicting Emperor Otto I presenting Magdeburg Cathedral to Christ, illustrating the imperial religiosity that contrasted with Atto's warnings against foreign intervention in Italy
License: * CC0 1.0 (Public Domain dedication – image courtesy of The Metropolitan Museum of Art

Historical Context and Contemporaries: Atto’s life spanned the dissolution of Carolingian order in Italy and the dawn of the Holy Roman Empire’s Italian involvement. He was contemporary with figures like Ratherius of Verona (c.887–974), another outspoken Lombard bishop; the two shared reformist and scholarly tendencies (Ratherius also wrote moral polemics). Atto corresponded with bishops across the Alps, and he likely knew of the monastic reform currents at Cluny (founded 910), given his own zeal for clerical integrity. Politically, he dealt with Hugh of Provence and Berengar II – rulers trying to unify Italy – and saw the transition to Ottonian dominance. A near-contemporary is Liudprand of Cremona (c.920–972), whose pro-Otto writings form a foil to Atto’s perspectives (www.degruyterbrill.com). Atto and Liudprand exemplify two Italian ecclesiastical viewpoints in that era: one prioritizing legitimacy and local autonomy (Atto), and the other welcoming imperial reform (Liudprand). Atto also lived through the “Iron Century” of the Papacy – the papal throne was weak and embroiled in Roman nobility feuds (John XII’s scandalous tenure began in 955). Though Atto’s works do not focus on the Papacy, he was aware of Rome’s plight and the need for moral reform in the clergy, which he addresses in his canons and letters (www.encyclopedia.com).

Legacy: Atto of Vercelli is remembered as a scholar-bishop who bridged the worlds of court and cloister. In his own time, he was respected as a learned canonist – later medieval canon law collections would use some of his diocesan statutes and letters as authoritative statements (www.catholicity.com). His writings, especially De pressuris and the Polypticum, have gained new appreciation for illuminating 10th-century conditions in Italy and the mentality of reforming churchmen before the Gregorian Reform. Atto’s emphasis on the spiritual autonomy of the Church (against lay confiscation) and on holding rulers accountable to Christian standards presaged the ideals of the 11th-century reformers (www.encyclopedia.com) (www.encyclopedia.com). Locally, Vercelli benefited from Atto’s tenure – he obtained privileges that strengthened the diocese’s temporal rights (www.catholicity.com) and likely improved education by fostering the cathedral school (indeed, Vercelli later produced the famous Vercelli Book of Old English sermons, perhaps indicating a strong scholarly scriptorium a generation after Atto). Though his Latin style fell out of favor (being too convoluted for later tastes), modern medievalists celebrate it as part of the 10th-century Latin renaissance. Today, Atto’s “labyrinthine” Polypticum, once on the margins, is considered a work of considerable cultural ambition that enhances our understanding of early medieval satire and episcopal ideology (cris.unibo.it) (www.degruyterbrill.com). In summary, Atto’s legacy is that of a courageous bishop who used his pen as well as his office to uphold moral order in a time of chaos – truly an index of his age, as one encyclopedia puts it (www.encyclopedia.com).