With the accession of Commodus (180–192), son of Marcus, the long and glorious period of the patriot emperors came to an end, and the ruin of the empire began. The foolish and headstrong boy, who was now lord of the Roman world, sacrificed some of the best generals in his service to his jealous and cowardly suspicions, and while he was devoting himself to the bloody pastimes of the amphitheatre, allowed the necessary work of the defence of the frontier to fall behind. “The tribes in the island of Britain,” we are told by Dion Cassius, “over-passed the wall which separated them from the Roman armies, committed widespread ravages, and cut to pieces a Roman general with the troops under his command.” Which of the two walls is here referred to is not easy to say. It may be conjectured, however, that the wall of Antoninus had been already broken down in the reign of Marcus, during the “heavily pressing” Britannic war, and that we have here a description of one of those barbaric demolitions of which we find such abundant traces in the wall of Hadrian. To chastise the barbarians and to restore the broken _Limes_ Commodus sent probably his best general, the sturdy old soldier, Ulpius Marcellus. If discipline were relaxed in the legions on the British frontier, here was certainly the man to restore it. St. Paul himself was not more resolute to “buffet his body and bring it into subjection” than this chief of many legions. A scanty sleeper himself, he framed ingenious plans to keep his centurions and officers at night harassed and awake. An old man with toothless and tender gums, he would eat only the stale hard bread which he had brought from Rome, in order that he might not fall into gluttony and excess. Such was the man who restored for a time the honour of the Roman arms, and who chastised the barbarians so thoroughly that all men marvelled that he was not, on his return to Rome, condemned to death by the jealous Commodus.