Usus Modernus

From Max-EuP 2012

by Klaus Luig

1. Background

The term usus modernus pandectarum designated, in the broadest sense, the entire period in European legal history in which the Roman law, as compiled by the Byzantine Emperor Justinian (527–567 CE), was regarded as binding in scholarship, doctrine and practice. According to this view, the usus modernus of Roman law began in 12th-century Italy with the glossators and was only brought to an end during the 19th century by the modern civil codes (codification).

If, however, the various eras and schools using the Justinianic law (Corpus Juris Civilis) are to be analysed more closely, a distinction can be drawn between the epochs of the glossators (1100–1250), the commentators (1250–1500), humanist jurisprudence (1500–1600), natural law (1650–1800), usus modernus in the narrow sense (1650–1800) and pandectism (1800–1900; Pandektensystem).

European development began with an age of ‘absolute’ Roman law, in which lawyers formulated the principle ‘omnia in corpore iuris inveniuntur’ or ‘hic liber comprehendit omnia iura’. By that time, however, the glossators had already started to adapt the Justinianic law to their own views and beliefs and thus, in a way, to establish an usus modernus. This process, never explicitly acknowledged, of a modernization was accomplished by generalizing the content of some texts and narrowly interpreting others. The commentators then undertook a deliberate modernization of the law through a rather liberal interpretation of the Roman texts.

The oath taken by the judges of the Reichskammergericht (Imperial Chamber Court), founded in 1495, represented the starting point of the development in Germany. With this oath, the judges undertook ‘to judge … according to the common laws of the Empire … and the fair and honourable individual ordonnances, statutes and customs of the principalities, sovereignties and courts, which are brought before them.’

This formula was based on the following doctrine of legal sources: the common law of the Empire included Justinian’s Corpus Juris Civilis, the Corpus Juris Canonici of the Roman Catholic Church (canon law) and the Libri Feudorum of feudal law. In particular, Roman law was regarded as having been adopted as imperial law by a statute of Emperor Lothar III of Supplinburg in 1137. The Roman law was only applicable in the absence of particular imperial statutes or the statutes in individual territories or towns. All of these legal sources had priority over Roman law. However, their applicability was limited because their validity for any given territory had to be proved by the party invoking it. In contrast, the common law (ius commune) was presumed to be applicable (fundata intentio) and was regarded to be within the knowledge of the court. In addition, the non-Roman rules were to be interpreted narrowly—with as little deviation from Roman law as possible. Finally, they had to be tested and found to conform to the boni mores.

2. Modernization

a) Doctrine of legal sources

The doctrine of legal sources just described was gradually replaced, from the middle of the 17th century onwards, by another theory and corresponding practice which sought to combine native law and Roman law. It characterized itself rather self-confidently as ‘modern-use’ (usus modernus) of Roman law.

The most important reason for this modernization was the laborious task of establishing the applicable law in every case that came before the court. This was criticized by Herman Conring (1606–81), a doctor and lawyer from Helmstedt. Conring observed that while Roman law had the most important place among the different sources from which the law of a particular case was to be derived, it was written in a foreign language and at the same time, in many respects, contrary to German values. Moreover, it comprised the opinions of the old Roman jurists, ie the jurists of the classical period of Roman law, rather than clear statutory rules and was therefore bedevilled by innumerable controversies.

The renewal and modernization began in 1643 with Conring’s proof that, contrary to the majority view, Roman law had not been adopted by a statute of Emperor Lothar III of Supplinburg in 1137. Rather, it had been received by custom, gradually and rule by rule, through practical use (usu sensim), and approved and affirmed by legislation. But what had been received through practical use could also, again, become obsolete by non-use.

If this was to be taken seriously, there could be no presumption of applicability (fundata intentio) of Roman law in every individual case. Strictly speaking, therefore, the reception of every particular rule had to be demonstrated. However, not all authors promoted such an extreme consequence of the modern understanding of the reception of Roman law. The more moderate view, widely adopted, was that there was a presumption in favour of the applicability of both Roman and native law (ius patrium). This compromise could only be applied to areas in which Roman and native law did not contradict one another but dealt with issues unknown to the other, ie Einkindschaft (equal treatment of children born to one parent from two different marriages), Leibgedinge (a kind of pension), Morgengabe (a gift from husband to wife on the morning after the wedding), Auflassung (agreement concerning the transfer of real property), etc. Insofar as native law contradicted Roman law—for instance, Roman law did not recognize representation, a well established concept in native law—a compromise recognizing two common laws was not possible. Such conflicts had to be settled case-by-case through legislation, judicial decision or doctrinal writing; and they required that Roman law was tested rule by rule for its conformity with German values. To a large extent, this was done by measuring the indigenous law against natural law. The natural law school had been active since the second half of the 17th century, simultaneously with that of the usus modernus. Its adherents started from the assumption that the local German law, deriving from native roots, was in complete agreement with the natural law.

Furthermore, the rules of native law no longer had to be interpreted restrictively; just as those of Roman law, they were capable of analogical extension. This played a role in the adoption of the principle, based on canon law, germanische Treue (German faithfulness) and natural law, that informal contractual agreements (pacta nuda) were to be enforceable. This, in turn, allowed the development of a general law of contract, quite independent of Roman law.

In the eyes of lawyers in the late 17th and 18th centuries, the usus modernus was not only designed to protect the native law from the infiltration of Roman law, but also to renew and adapt the rules and institutions of Roman law, the reception of which was not denied by the proponents of such renewal. The boundary between genuinely indigenous rules on the one hand, and those which were received, and then adapted to contemporary requirements, on the other, cannot always easily be drawn. However, such a distinction is necessary because the really interesting aspect of the usus modernus pandectarum is the adaptation of Roman law to modern conditions. Since no distinctive period for the rise of the native ius germanicum can be identified, both phenomena, in combination, characterize the era normally referred to as usus modernus. For the purposes of this entry, even those native institutions, which, because they were more modern, prevailed over rules received from Roman law, have to be considered as fruits of the usus modernus.

b) Examples of modernization

The seller’s right to set aside a sale for laesio enormis (C. 4,44,2) was initially received from Roman law but then extended to buyers by an interpretation intended to adapt the rule to modern requirements. There was also evidence of an usus modernus pandectarum in the deduction of a general clausula rebus sic stantibus from two special cases preserved in the Digest (D. 12,4,8 and D. 46,3,3 pr.), a process which began in the Middle Ages. In a similar way, the decision of questions of contributory negligence according to the predominant fault of one of the parties, rather than according to the rule in the ‘barber case’ in D. 9,2,11, according to which even minor contributory fault excludes liability, can be seen as the creation of a usus modernus of a rule of Roman law (Roman law).

A liberalizing tendency is illustrated by the modernization of the rules on transfer of ownership concerning contracts of sale. In order to allow a transfer of ownership although the purchase price had not been paid, the granting of credit that was required was presumed to have occurred by the proponents of the usus modernus despite the absence of any basis for such rule in the Roman texts.

Similarly, an assignee was no longer considered to be a mere procurator, but rather as being truly entitled to the right assigned to him. Here, as in other cases, the modern solution to a problem of the Roman law, as it had been received, was supported from the point of view of Germanic or natural law.

c) The ‘purging’ of Roman law

The usus modernus was not just based on the extension of Roman law to new situations. It was also concerned with ‘purging’ (Bernhard Windscheid) Roman law of limitations which were no longer appropriate. Insofar as Roman rules were thus rendered obsolete, it was said that the ‘subtleties’ of Roman law had never been received or had at least been derogated from in the course of its modernization. This applied, for instance, to the duplum penalties of Roman law. Another example of the abandonment of specific rules limiting commercial freedom was the derogation—established by case law—of the prohibition on assignment to someone in authority over the debtor (cessio in potentiorem) based on C. 2,13,1. The lex Anastasiana (C. 4,35,22) preventing an assignee from exercising a right at a higher price than he had paid himself. Though just as significant for commerce, it resisted all attempts at modernization. A further modernization lay in the abolition of the prohibition on the accumulation of interest beyond the amount of the capital which was owed (ultra alterum tantum or, more precisely, ultra sortis summam (C. 4,32,10; interest)). The Roman restriction limiting fideicommissa (trusts) to four generations also failed to prove suitable for modern times. Moreover, the assessment rules concerning damages claims under the lex Aquilia fell victim to the modernizers’ reforms.

The starting point for the introduction of innovations was often the law of a particular town or territory. The lawyers of the usus modernus were able to take rules from one place to another, extending their physical area of application, and they were also able to generalize the interpretation of rules found in different places. A rule that could be found in many territories, could thus be extended to an area where there was no concrete evidence of its use. In regard to the validity of particular rules, lawyers of the usus modernus inferred ubique in Germania from fere ubique in Germania. Thus, there were rules of customary law valid across the whole of Germany (consuetudines universales or generales). Insofar as these had no counterpart in Roman law and were not related to it, they were, from the 18th century onwards, presented under the name of Deutsches Privatrecht as an autonomous system of private law, separate from Roman law.

If an attempt is made to summarize the predominant substantive tendencies of the usus modernus, the general impression is that the lawyers of the usus modernus generally sought to create a liberal law, suitable for commercial relations and focusing on the will of the parties. The greatest achievement of the usus modernus was the scholarly penetration of the system of private law and the consolidation, and integration, of legal practice. On this basis, a modern ius commune was created, which laid foundations for the system of private law which have remained important until today. Consequently, rules of Roman, German, canon and natural law origin as well as modern statutory and (judicial) customary law formed a uniform legal system developed in a scholarly fashion.

3. Textbooks

The cumulative effect of these innovations made a new type of textbook necessary. Conring rejected the predominant approach of producing commentaries on the Justinianic Digest. Instead, he set out to write a concise handbook, an exiguus libellus, covering the whole of the law in force but leaving out all of the materials which were no longer useful. It only contained what either as customary law (German law) or as written law (Roman-canon law) was used in practice. The Institutes coutumières by the Frenchman Antoine Loisel (1536–1617), which appeared in 1607, may be seen as a forerunner of this kind of treatise. Comparable accounts of the law in force, which can be characterized as institutional textbooks, were thereafter published at an increasing rate. Essentially, they constituted first steps on the way towards the subsequent codifications. Their authors used a modified version of the scheme underlying Justinian’s Institutes as their model. The rules of Roman law, which had become obsolete, were left out, while those without a Roman law basis, such as insurance, contracts of inheritance (contracts of inheritance and joint wills) and gambling, were inserted at appropriate places.

One of the earliest of these works was Hugo Grotius’ (1583–1645) Inleidinge tot de Hollandsche rechtsgeleerdheid (Roman-Dutch law). Grotius followed the example of Justinian’s Institutes and divided his work into three parts: persons, things and succession, and obligations. He did not deal with the law of actions. Throughout, attention was drawn to the modern use made of the rules of Roman law. Into this system, at the appropriate points, he inserted both institutions of specifically Dutch origin and those with more widespread areas of application such as the law relating to interest, shipping, sailors, insurance, the law of average, and the law of currency exchange.

Georg Adam Struve’s (1619–92) influential Juris-Prudenz, oder: Verfassung der landüblichen Rechte (1689) followed the same model. The same approach was maintained in further editions, in 1696 and 1711. The work incorporated—within a slightly modified institutional scheme with chapters on persons and things, including succession and obligations—such native institutions as insurance, bottomry loan, contracts of succession, liability for defects in animals, gambling, redemption, interest and feudalism. An abridgement of ‘Juris-Prudenz’ was revised and re-published many times under the title Jurisprudentia Romano-Germanica between 1670 and 1771. However, the entire era takes its name from a commentary on the Digest by Samuel Stryk (1640–1710) entitled Usus modernus Pandectarum, the first volume of which appeared in 1690. It fulfilled the ambition of contemporary lawyers so well that the title of the work could be used to designate the whole period. The Roman-national (ie Roman-Dutch and Roman-German, but also Roman-Neapolitan, Roman-French, Roman-Hispanic etc) institutional works (institutional textbooks) spread across the whole of Europe in the 18th century.


Franz Wieacker, Privatrechtsgeschichte der Neuzeit (2nd edn, 1967); Wolfgang Wiegand, Studien zur Rechtsanwendungslehre der Rezeptionszeit (1977); Klaus Luig, ‘Conring, das deutsche Recht und die Rechtsgeschichte’ in Michael Stolleis (ed), Hermann Conring (1606–1681) (1983) 355; also in Klaus Luig, Römisches Recht, Naturrecht, Nationales Recht (1998) 219; Helmut Coing, Europäisches Privatrecht, I Älteres gemeines Recht 1500–1800 (1985); Tony Weir (tr), Franz Wieacker, A History of Private Law in Europe (1995); Hermann Lange, Römisches Recht im Mittelalter, vol I: Die Glossatoren (1997); Klaus Luig, ‘Samuel Stryk und der “Usus modernus Pandectarum”’ in Festschrift Sten Gagnér (1998) 219; also in Klaus Luig, Römisches Recht, Naturrecht, Nationales Recht (1998) 91; Peter Oestmann, Rechtsvielfalt vor Gericht (2002); Hermann Lange and Maximiliane Kriechbaum, Römisches Recht im Mittelalter, vol II: Die Kommentatoren (2007); Hans-Peter Haferkamp and Tilman Repgen (eds), Usus modernus Pandectarum: Römisches Recht, Deutsches Recht und Naturrecht in der frühen Neuzeit (2007); Frank L Schäfer, Juristische Germanistik, eine Geschichte der Wissenschaft vom einheimischen Privatrecht (2008).


Hugo Grotius, Inleiding tot de hollandsche rechts-geleerdheid (1631); Hermann Conring, De origine iuris Germanici (1643); Antoine Loisel, Institutes coutumières (1646); Samuel Styrk, Usus modernus Pandectarum, vol I-III (1690-1712).

Retrieved from Usus Modernus – Max-EuP 2012 on 27 May 2022.

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