IRNERIO. – Bolognese jurist (12th century). With him, together with the Studium of Bologna and the school of the glossators, began the entire renewal of studies aimed at giving Roman law a second life and at laying the doctrinal foundations of the ius commune.
Little information is available about the life of I. Thirteen documents dating from 1112 to 1125 show him first as a causidicus and then as a judge, whose learning was consulted, among others, by Countess Matilde and the Emperor Arrigo V. I. with a namesake missus domini imperatoris mentioned in 1100 is highly improbable; and every attempt to date his life and activity beyond the limits indicated belongs to the realm of hypothesis.
According to traditions reported a century after his time by the chronicler Burcardo d'Ursperg and the glossator Odofredo, I., initially magister in artibus, later turned to legal studies and, at the invitation of Countess Matilde, brought to light in their genuine form the texts of Justinian law, until then neglected: primus illuminator scientiae
nostrae (as Odofredo put it). In a short time he eclipsed the reputation of his sole predecessor Pepo, drawing to Bologna through his teaching the large concourse of students which, already during his lifetime, earned the city the epithet of docta.
Of the writings attributed to I., only the glosses on the Corpus iuris civilis—and not all of them—are certainly his: some are included in the great apparatus of Accursius, while others are cited by other jurists or preserved separately in manuscripts that long remained unknown. Secure attribution is often impeded by the variety of sigla marking Irnerian glosses in the manuscripts and corresponding to the various forms in which the name appears. The sigla G., Gar., Garn., Girn., Guar., Guarn., Var., War. belong to the original form Guarnerio; the more recent form I., whose relationship to the other has been variously explained, is represented by Hyr., I., Ir., Y., Yr., though these are not all certainly exclusive to I. Although he was not the first to gloss the Roman texts, as tradition wrongly asserted, he was the one who extended this method of teaching to all parts of the Corpus iuris, which he restored to its ancient unity thanks to the discovery of the Infiorium (II. XXIV–XXXVIII of the Digest) and substituted for the epitomes in vogue in the early Middle Ages; above all, he was the first to investigate deeply the legal content of those texts.
I. also played an important part in the compilation of the so-called «authenticae», excerpts from Justinian’s Novels inserted into the Code in the appropriate places.
It is also known that I. wrote other works, of greater scope: a notarial formulary, a collection of quaestiones, and a treatise de actionibus; all are lost. The attributions to him of the Summa Infortiati, the Brachylogus, the Epitome exactis regibus, the Formularium tabellionum, the Quaestiones de iuris subtilitatibus, the De aequitate, the Qui de re pecuniaris, the Summa legis Langobardorum, the Summa codicis Trecensis, the Summa institutum Fundobonensis, and the Liber divinarum sententiarum are today generally rejected by critical scholarship; they are explained by the desire to give a more concrete form to the almost legendary figure of the man who was called lucerna iuris.
BIBL. P. C. von Savigny, Geschichte des römischen Rechts im Mittelalter, IV, 2nd ed., Heidelberg 1895, pp. 9 ff., 458 ff.; C. Ricci, I primordi dello Studio di Bologna, 2nd ed., Bologna 1888, pp. 26 ff., 137 ff.; G. Pescatore, Die Glossen des Irnerius, Grafswald 1888; E. Besta, L'opera d'I., Torino 1896; H. Kantorowicz, Studies in the glossators of the roman law, Cambridge 1938, pp. 33 ff., 233 ff.; L. Simeoni, Un nuovo documento
su I. del 1912, in Atti e memorie della Dep. di storia patria per l'Emilia e la Romagna, 4 (1939), p. 5 ff.; P. Torelli, Glosse preaccurviane alle Istituzioni: nota prima; glosse d'I., negli Studi in onore di Dorice Besta, IV, Milano 1939, p. 229 ff. Piero Fiorelli