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Attractively presented legal incunable - one copy in North America

Attractively presented legal incunable - one copy in North America

£18,000 €21,000 | $23,000

Baysio, Guido de [ed. Petrus Albinianus Trecius, with additions by Paulus Pisanus]: Rosarium decretorum. Venice: Reynaldus de Novimagio, 12 December 1480.


This scarce incunable – one of just 22 located copies worldwide – is a particularly attractive copy of the third edition of Guido de Baysio’s important commentary on Gratian’s Decretum, a foundational collection of canon law. This incunable is impressively rubricated and sheds interesting light on working practices in medieval book decoration, and survives in a late sixteenth- or early seventeenth-century binding with particularly intricate blind-tooled decoration. The edition has interesting new letters at beginning and end and the copy has early marginalia and handwritten corrections. 


One volume, folio, 41 x 29.5 cms (in binding), ff. 415 [lacks final blank]. Accurate foliation in pencil on every hundredth folio. Collation: a-d10 ძ e6 f10 g-l8 m n6 o-v u x8 y-z10 ⁊ ↄ 8 aa bb10 cc8 dd ძძ-ff ffff gg-ii10 kk8 ll10 mm nn8 oo-qq10 rr8 ss6 [lacks blank ss6]. Text mostly in two columns.


Approx. 20 large decorative initials in red and blue (typically c.8 lines in height). Smaller rubricated initials in red or blue throughout. A mixture of printed and handwritten guide letters often visible. Occasional adjustments to rubrication in dark brown ink (see discussion below). Running titles on rectos in red (sometimes shaved).


Materials: late sixteenth- or early seventeenth-century alum-tawed pigskin over wooden boards.

Decoration: Both covers tooled in blind, the design comprising a centrepiece and rolls inside three concentric frames. Upper cover centrepiece: coat of arms of St Michael’s Abbey, Metten (= Einbanddatenbank p003351)This tool is listed in Einbanddatenbank as the arms of Johannes Christoph Guetknecht, abbot of St Michael’s Abbey (1628-1645). We believe that this is an error, perhaps extrapolated from m001804 (where the same coat of arms is accompanied with Guetknecht’s initials and the year 1629). In his detailed study of Bavarian monastic heraldry, E. Zimmermann records a different coat of arms for abbot Guetknecht, and moreover the coat of arms he records for the abbey (in use from 1548 onwards) matches the one found on the present binding (Zimmermann 1930, pp. 102-3). Lower cover centrepiece: St Michael the Archangel (= Einbanddatenbank p003350). Innermost roll: biblical scenes including the crucifixion and Christ emerging from the tomb (= Einbanddatenbank r004246). Compare also r003712, associated with the workshop of 'A. O.' (w004465; Haebler I 316). Middle roll: heads in profile alternating left and right. Cockx-Indestege records a nineteenth-century note in French in our book suggesting that this roll depicts the Farnese popes: ‘....orné de médaillons représentant les papes de la famille des farnese’ (2003, no. 68). We note similarities to r003713, likewise associated with the aforementioned workshop of 'A. O.' Outermost roll: floral pattern. For the overall design, compare also the binding descriptions for Bodleian Library Auct. 6Q 3.30,31 and British Library IC22666. We have consulted BL IC22666 and note that it is very similar to the present binding, using identical tools for at least the middle roll and lower cover centrepiece. 

Fastenings: Replacement fastenings (the strap and at least some of the old metal replaced). Leather lifting slightly from inside of both straps.

Lettering: Author and title, imprint location, and possible shelfmark respectively lettered to the first, second, and fifth spine compartments (faded).

Endpapers: The second free endpaper at the front, both free endpapers at the rear, and the rear pastedown were all added during the rebinding phase in the late sixteenth or early seventeenth century, at which point the edges of the book were painted red. A front pastedown was also added at this stage, observable under present pastedown. The current front pastedown and front free endpaper were added perhaps at time of repair (infill to worm holes on front board) at which point an attempt was also made to give the new front free endpaper matching red edges. 

Edges: Red edges.

Condition of binding: Overall well preserved, with some worming to both covers (mostly infilled), crack to upper joint at base of spine, a few scratches to lower cover.

Condition (textblock)

Headlines and marginalia sometimes shaved. Worming at start and end of textblock (often in blank areas, but at most affecting about a dozen letters per page). Light browning and foxing, occasional small tears and losses to blank outer margins. 


  1. A handful of early marginalia in one or perhaps two hands, including neatly executed manicules. Perhaps connected are at least two handwritten corrections to the printed text (sigs. mm3v, ss1r) and ‘corrections’ to rubrication (see discussion below).  
  2. Formerly in the library of St Michael’s Abbey, Metten (OSB), which was dispersed in the early nineteenth century during secularisation. Inscription: ‘Iste liber e[st] S. Michaelis Archangeli Patroni in Metten (sig. a2r). Cf. the coat of arms on the binding, as described above. The Material Evidence in Incunabula database records 11 incunables formerly in this library, with the present holding institutions including the British Library, the Bodleian Library, and the Houghton Library.
  3. Traces of bookplate or label on the second free endpaper, with faded pencil notes below. Further pencil notes to pastedowns (cf. binding description above).
  4. Albert Ehrman (1890–1969), acquired from Antiquariaat Marechal in Bruges. See Cockx-Indestege 2003, no. 68. Ehrman was the builder of the Broxbourne Library, a collection dedicated to the history of European printing and the book trade, of which there are segments found in the Bodleian and Cambridge University libraries. See A. S. G. Edwards (2010).
  5. Sotheby's (14 May 1979, lot 17). Buyer: J.A. Joseph.
  6. Christie’s (30 November 2010, lot 66).
  7. Hugues de Latude (see reference to our copy in GW).


Guido de Baysio (d.1313), often known as Archidiaconus in reference to his position of Archdeacon of the Church of Bologna, received his doctorate in canon law at Reggio. He went on to teach students including the celebrated Johannes Andreae (d. 1348), and also became a papal chaplain. His commentary on Gratian’s Decretum, completed c.1300, ‘makes extensive use of some doctrinal sources that had been ignored in the Ordinary Glossa […], in particular the work of Laurentius Hispanus’ (Padoa-Schioppa 2017, p. 104). It is described as Baysio’s most important work by the jurist Tommaso Diplovatazio (1468-1541) in his work on famous lawyers, unpublished until the twentieth century, De claris iuris consultis.

The Rosarium was first printed in Strassburg c.1473, with the second edition printed in Rome in 1477. This third edition was the first to be edited by Petrus Albinianus Trecius, an Italian jurist originally from Treccio sull'Adda, who studied at the University of Padua. A letter to Trecius appended to the text suggests that the work was still rare on people's shelves. Paolo Pisani, an Augustinian writing from Vicenza – and apparently a relative of the senator Paolo Pisani (d. 1509) – erroneously laments that Baysio’s important commentary has yet to be printed.

Trecius’s reply, also included, notes: ‘it is truly full of roses and flowers…’ (Rosis enim et floribus plenum est…). Interestingly, this praise appears almost verbatim in Diplovatazio’s aforementioned De claris iuris consultis (p. 191), suggesting that Trecius and Diplovatazio drew on a common source, and thus used words to describe the book that would no doubt have been recognised by other legal professionals.

Also new to this edition is Trecius’s dedicatory letter to Cardinal Francesco Piccolomini (the future Pope Pius III). Here, Trecius makes use of a common editorial trope by explaining that he found and rectified almost innumerable errors (innumeros tamen pene errores repperi). Interestingly, this dedicatory letter effectively became part of the textual tradition of the Rosarium decretum, as it was also included in a reprint of the 1495 edition (see GW 03748 anm. 1).

The epistolary material new to this edition offers an example of a wider contemporary phenomenon, namely the addition of humanistically styled letters to professional legal publications. They also give a sense of the network of people to which our copy editor belonged—or indeed aspired to belong.

This edition also includes a quire register on the final leaf. It lists the incipits of all rectos in the first half of each quire, which would have been a useful reference tool for the binder. In the case of quire a (for which the first recto is blank) the register instead records: ‘primu[s] vacat’. We note that there is no such quire register in the first edition, while a similar register would later appear in the fourth edition (1481).

Our edition was printed by Reynaldus de Novimagio (active 1477-1496), a Venetian printer whose later career overlapped with the infancy of the celebrated Aldine press. ‘Novimagus’ may refer to Nijmegen (Novimagus Batavum; today in the Netherlands), Neumagen (Germany), or Speyer (Noviomagus Nemetum; Germany), with the latter fitting ‘extremely well with the whole company of people active in Venice’ (cf. Coppens 2014, p. 117). The present incunable is relatively typical of Reynaldus de Novimagio’s output, which consisted primarily of scholarly folio editions.

In spite of Trecius’s efforts to correct the text of the Rosarium decretorum, errors remained. We note two corrections by hand in this copy, suggesting that close attention was paid to the text.

These corrections may be connected with the late fifteenth- or early sixteenth-century annotating hand (or perhaps two hands?) found elsewhere in the volume. There are about half a dozen instances of marginalia, often comprising a neatly drawn manicule and sometimes accompanied by a short note or some underlining. These occur sporadically throughout the volume, which is consistent with its use as a reference text. The longest annotation occurs at a section of the text discussing original sin: 

Perhaps the most intriguing example is an annotation and manicule that flag a passage of text relating to menstruation. In this section of the text, menstrual blood is conceptualized as a source of contamination, capable of ruining crops and driving dogs rabid (on the origin of these ideas, see Green 2006, p. 557). We also note that this passage engages with ideas about sexual intercourse during menstruation being a cause of leprosy. 

This copy is also notable for its elaborate hierarchy of decoration. Major textual divisions are signalled by large initials in red and blue, whereas smaller textual divisions are signposted with initials in red or blue (typically alternating). To further help the reader navigate the text, the printed running titles have been supplemented by the rubricator with other paratextual apparatus.

This decoration offers a fascinating window onto the working practices behind medieval rubrication, especially the methods for planning—and how they could go awry. Rubricators often relied on guide letters to indicate the initial that they needed to supply. While the first edition of Rosarium decretorum had included printed guide letters throughout, in this third edition printed guide letters were offered generally only for the larger initials (though this is not a hard and fast rule). These printed guide letters have been supplemented in our copy with handwritten examples, offering the opportunity to compare the two types alongside each other.

Some of these printed guide letters, e.g. S, were conveniently (and, it would seem, deliberately) concealed within the letter forms of the decorative initial, though others (notably Q) did not always present this opportunity. A similar impetus towards subtlety can arguably be found in the handwritten guide letters, which were added only very faintly. These supplementary handwritten guide letters were quite possibly added by an individual who handled the book before it reached the rubricator, as suggested by the miscommunications between the two that we will shortly encounter.

While the overall effect of the rubrication in this incunable is clearly highly impressive, closer inspection reveals the fascinating potential for human error in this process. For example, the guide letter F for Frater has mistakenly been rendered as P:

Amid a particularly compact section of decoration on the same folio, the rubricator seems to have overlooked one guide letter entirely and wrongly rendered another. The sequence should apparently have the following six initials: ‘Siquis… Si forte … Qui rapit … Pecunia … Siquis … Nullorum…’. However, the initial Q for ‘Qui rapit’ has been passed over, and Pecunia has mistakenly become Recunia. The rubricator’s four-line S could arguably serve to economically cover the first two initials required, or is perhaps yet another mistake.

Other errors originated when the guide letters themselves were added, and were simply perpetuated (rather than introduced) during rubrication process. In the example below, we can discern the very faint guide letter I that informed the rubricator’s blue initial. It appears that an observant reader creatively transformed this into an A, such that the word correctly reads ‘Anteriorum’ rather than Interiorum. In practice, we can therefore detect at least four or five individuals effectively collaborating across time to make this word on the page: the compositor who set the body text, the puller who operated the printing press, the scribe who added the guide letter, the rubricator who added the initial, and the reader who ultimately corrected it.

The same reader appears to be responsible for supplying an initial N that was omitted entirely, and an S that is only faintly visible. In both cases, the reader attempts to match the style (if not the colour) of the missing initials:

Within two centuries of the book being printed (and perhaps indeed earlier), it reached Germany and became part of the library of the Benedictine Abbey in Metten. The coat of arms of the abbey features on the upper cover of the late sixteenth- or early seventeenth-century binding, and the centrepiece on the lower cover depicts St Michael the Archangel, after whom the abbey was named. An inscription also confirms the association. The contents of this library were dispersed in the early nineteenth century during secularisation.

The tools used on this binding are a particularly intricate example of late sixteenth- or early seventeenth-century German binding decoration. We note especially the level of detail in the biblical scenes represented in the roll used on the innermost frame.

Some of these tools are recorded in Einbanddatenbank, but not in connection with an identifiable workshop. For comparison, very similar rolls are associated with the workshop of 'A.O'. Haebler suggests that this could be Andreas Obermayer the younger, a Nuremberg bookbinder (d.1616). Given that Metten abbey is located only about 100 miles away from Nuremberg, it is tempting to speculate that the abbey commissioned the binding from a workshop there. Deggendorf has also been suggested as a possibility for the binding (see Cockx-Indestege 2003, no. 68). 

Overall, this incunable is notable not only for its rarity, but also for the rich and diverse range of examples it offers in terms of early book production and use. 


ISTC ib00287000. GW 3746. BMC V 256. [We note a collation error in the digital version of GW; there should be no second quire e, as correctly described in the print version].   

Between them, ISTC, GW and OCLC show 21 copies in public institutions, of which only three outside mainland Europe (British Library, Brompton Oratory Library, and Trinity College, Hartford, Connecticut (Watkinson Library). This is the only located copy in trade (seen twice before at auction, 1979, 2010).

Cockx-Indestege, Elly, 'Classica et humanistica: een Belgische incunabelcollectie uit de twintigste eeuw', De gulden passer 81 (2003) 1-113. Accessed here.

Coppens, Christian, ‘Giovanni da Colonia, Aka Johann Ewylre/Arwylre/Ahrweiler: the Early Printed Book and its Investors’, La Bibliofilia 116 (2014), 113-20.

Diplovatazio, Tommaso, De claris iuris consultis, in Schulz, Fritz, Hermann Kantorowicz, and Giuseppe Rabotti (eds.), Thomae Diplovatatii Liber de claris iuris consultis. Pars posterior (Bononiae, Institutum Gratianum 1968).

Edwards, A. S. G., ‘Ehrman, Albert’, in Michael F., Suarez and H. R. Woudhuysen (eds.), The Oxford Companion to the Book, 2 vols. (Oxford: OUP, 2010), II, 692.

Einbanddatenbank (Staatsbibliothek zu Berlin), accessed via

Granitsas, Margot, ‘Books in a Gilded Cage’, New York Times, 3 December 1989.

Green, Monica H., 'Menstruation', in Margaret Schaus (ed.), Women and Gender in Medieval Europe: An Encyclopedia (New York and London, Routledge, 2006), pp. 557-558. 

Haebler, Konrad, Rollen- und Plattenstempel des XVI. Jahrhunderts: Unter Mitwirkung von Dr Ilse Schunke (Leipzig, O. Harrassowitz, 1928-1929).

KP (rev BP 2015), ‘Report No. r268, Guido de Baysio, c.1246/1256–1313’, Bio-Bibliographical Guide to Medieval and Early Modern Jurists, accessed here.

Padoa-Schioppa, Antonio, A History of Law in Europe: From the Early Middle Ages to the Twentieth Century (Cambridge, Cambridge University Press, 2017), p. 104.

Rosa, Mario, ‘Albignani, Pietro’, Dizionario Biografico degli Italiani 2 (1960), accessed via

Zimmermann, E., Bayerischer Kloster-Heraldik. Die Wappen der Äbte und Pröpste der bis zum allgemeinen Säkularisation in Ober- und Niederbayern, der Oberpfalz und bayerisch Schwaben bestandenen Herrenkloster, etc. (München, 1930).

On the secularisation of Metten abbey, at which point the library was dispersed, we note the following resource (not consulted by us): Michael Kaufmann, Säkularisation, Desolation und Restauration in der Benediktinerabtei Metten (Metten: Abtei-Verlag, 1993).

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