Many of the causes which helped to mitigate the stringency of the father's power over the persons of his children are doubtless among those which do not lie upon the face of history. We cannot tell how far public opinion may have paralysed an authority which the law conferred, or how far natural affection may have rendered it endurable. But though the powers over the _person_ may have been latterly nominal, the whole tenour of the extant Roman jurisprudence suggests that the father's rights over the son's _property_ were always exercised without scruple to the full extent to which they were sanctioned by law. There is nothing to astonish us in the latitude of these rights when they first show themselves. The ancient law of Rome forbade the Children under Power to hold property apart from their parent, or (we should rather say) never contemplated the possibility of their claiming a separate ownership. The father was entitled to take the whole of the son's acquisitions, and to enjoy the benefit of his contracts without being entangled in any compensating liability. So much as this we should expect from the constitution of the earliest Roman society, for we can hardly form a notion of the primitive family group unless we suppose that its members brought their earnings of all kinds into the common stock while they were unable to bind it by improvident individual engagements. The true enigma of the Patria Potestas does not reside here, but in the slowness with which these proprietary privileges of the parent were curtailed, and in the circumstance that, before they were seriously diminished, the whole civilised world was brought within their sphere. No innovation of any kind was attempted till the first years of the Empire, when the acquisitions of soldiers on service were withdrawn from the operation of the Patria Potestas, doubtless as part of the reward of the armies which had overthrown the free commonwealth. Three centuries afterwards the same immunity was extended to the earnings of persons who were in the civil employment of the state. Both changes were obviously limited in their application, and they were so contrived in technical form as to interfere as little as possible with the principle of Patria Potestas. A certain qualified and dependent ownership had always been recognised by the Roman law in the perquisites and savings which slaves and sons under power were not compelled to include in the household accounts, and the special name of this permissive property, Peculium, was applied to the acquisitions newly relieved from Patria Potestas, which were called in the case of soldiers Castrense Peculium, and Quasi-castrense Peculium in the case of civil servants. Other modifications of the parental privileges followed, which showed a less studious outward respect for the ancient principle. Shortly after the introduction of the Quasi-castrense Peculium, Constantine the Great took away the father's absolute control over property which his children had inherited from their mother, and reduced it to a _usufruct_, or life-interest. A few more changes of slight importance followed in the Western Empire, but the furthest point reached was in the East, under Justinian, who enacted that unless the acquisitions of the child were derived from the parent's own property, the parent's rights over them should not extend beyond enjoying their produce for the period of his life. Even this, the utmost relaxation of the Roman Patria Potestas, left it far ampler and severer than any analogous institution of the modern world. The earliest modern writers on jurisprudence remark that it was only the fiercer and ruder of the conquerors of the empire, and notably the nations of Sclavonic origin, which exhibited a Patria Potestas at all resembling that which was described in the Pandects and the Code. All the Germanic immigrants seem to have recognised a corporate union of the family under the _mund_, or authority of a patriarchal chief; but his powers are obviously only the relics of a decayed Patria Potestas, and fell far short of those enjoyed by the Roman father. The Franks are particularly mentioned as not having the Roman Institution, and accordingly the old French lawyers, even when most busily engaged in filling the interstices of barbarous custom with rules of Roman law, were obliged to protect themselves against the intrusion of the Potestas by the express maxim, _Puyssance de père en France n'a lieu_. The tenacity of the Romans in maintaining this relic of their most ancient condition is in itself remarkable, but it is less remarkable than the diffusion of the Potestas over the whole of a civilisation from which it had once disappeared.