The Roman law always existed in the Middle Ages. Provincialized and changed, it was interwoven in the law and custom of the land of the _langue d’oc_ and even in the customary law of the lands where the _langue d’oil_ was spoken. Through the same territory it existed also in the _Breviarium_ and its epitomes. There was very little of it in England, and scarcely a trace in the Germany east of the Rhine. In Italy it was applied when not superseded by the Lombard codes, and was drawn from works based on the _Codex_ and _Novels_ of Justinian. But the jurisprudential law contained in Justinian’s _Digest_ was as well forgotten in Italy as in any land north of the Alps, where the Codification of Justinian had never been promulgated. The extent to which the classic forms of Roman law were known or unknown, unforgotten or forgotten, was no accident as of codices or other writings lost accidentally. It hung upon larger conditions--whether society had reached that stage of civilized exigency demanding the application of an advanced commercial law, and whether there were men capable of understanding and applying it. This need and the capacity to understand would be closely joined.[371] The history of the knowledge and understanding of Roman law in the Middle Ages might be resolved into a consideration of the sources drawn upon, and the extent and manner of their use, from century to century. In the fifth century, when the Theodosian Code was promulgated, law was thought of chiefly as the mandate of a ruler. The Theodosian Code was composed of _constitutiones principum_. Likewise the _Breviarium_, based upon it, and other barbarian codes of Roman law, were ordained by kings; and so were the codes of Teutonic law. For law, men looked directly to the visible ruler. The _jus_, reasoned out by the wisdom of trained jurists, had lost authority and interest. To be sure, a hundred years later Justinian’s Commission put together in the _Digest_ the body of jurisprudential law; but even in Italy where his codification was promulgated, the _Digest_ fell still-born. Never was an official compilation of less effect upon its own time, or of such mighty import for times to come. The _Breviarium_ became _par excellence_ the code of Roman law for the countries included in the present France. With its accompanying _Interpretatio_ it was a work indicating intelligence on the part of its compilers, whose chief care was as to arrangement and explanation. But the time was not progressive, and a gathering mental decadence was shown by the manner in which the _Breviarium_ was treated and used, to wit, epitomized in many epitomes, and practically superseded by them. Here was double evidence of decay; for the supersession of such a work by such epitomes indicates a diminishing legal knowledge in the epitomizers, and also a narrowing of social and commercial needs in the community, for which the original work contained much that was no longer useful.