The beloved son of Marcus succeeded to his father, amid the acclamations of the senate and armies; and when he ascended the throne the happy youth saw round him neither competitor to remove nor enemies to punish. In this calm, elevated station it was surely natural that he should prefer the love of mankind to their detestation, the mild glories of his five predecessors to the ignominious fate of Nero and Domitian.

Yet Commodus was not, as he has been represented, a tiger born with an insatiate thirst of human blood, and capable, from his infancy, of the most inhuman actions. Nature had formed him of a weak rather than a wicked disposition. His simplicity and timidity rendered him the slave of his attendants, who gradually corrupted his mind. His cruelty, which at first obeyed the dictates of others, degenerated into habit, and at length became the ruling passion of his soul.

Upon the death of his father, Commodus found himself embarrassed with the command of a great army, and the conduct of a difficult war against the Quadi and Marcomanni. The servile and profligate youths whom Marcus had banished soon regained their station and influence about the new Emperor. They exaggerated the hardships and dangers of a campaign in the wild countries beyond the Danube; and they assured the indolent prince that the terror of his name and the arms of his lieutenants would be sufficient to complete the conquest of the dismayed barbarians, or to impose such conditions as were more advantageous than any conquest. By a dexterous application to his sensual appetites they compared the tranquillity, the splendor, the refined pleasures of Rome with the tumult of a Pannonian camp, which afforded neither leisure nor materials for luxury. Commodus listened to the pleasing advice, but while he hesitated between his own inclination and the awe which he still retained for his father's counsellors, the summer insensibly elapsed, and his triumphal entry into the capital was deferred till the autumn. His graceful person, popular address, and imagined virtues attracted the public favor; the honorable peace which he had recently granted to the barbarians diffused a universal joy; his impatience to revisit Rome was fondly ascribed to the love of his country; and his dissolute course of amusements was faintly condemned in a prince of nineteen years of age.

During the three first years of his reign the forms, and even the spirit, of the old administration were maintained by those faithful counsellors to whom Marcus had recommended his son, and for whose wisdom and integrity Commodus still entertained a reluctant esteem. The young prince and his profligate favorites revelled in all the license of sovereign power; but his hands were yet unstained with blood; and he had even displayed a generosity of sentiment which might perhaps have ripened into solid virtue.[47] A fatal incident decided his fluctuating character.

One evening, as the Emperor was returning to the palace through a dark and narrow portico in the Amphitheatre, an assassin, who waited his passage, rushed upon him with a drawn sword, loudly exclaiming, "The senate sends you this." The menace prevented the deed; the assassin was seized by the guards, and immediately revealed the authors of the conspiracy. It had been formed, not in the state, but within the walls of the palace. Lucilla, the Emperor's sister, and widow of Lucius Verus, impatient of the second rank, and jealous of the reigning empress, had armed the murderer against her brother's life. She had not ventured to communicate the black design to her second husband, Claudius Pompeianus, a senator of distinguished merit and unshaken loyalty; but among the crowd of her lovers—for she imitated the manners of Faustina—she found men of desperate fortunes and wild ambition, who were prepared to serve her more violent as well as her tender passions. The conspirators experienced the rigor of justice, and the abandoned princess was punished, first with exile, and afterward with death.

But the words of the assassin sunk deep into the mind of Commodus, and left an indelible impression of fear and hatred against the whole body of the senate. Those whom he had dreaded as importunate ministers he now suspected as secret enemies. The delators, a race of men discouraged and almost extinguished under the former reigns, again became formidable, as soon as they discovered that the Emperor was desirous of finding disaffection and treason in the senate. That assembly, whom Marcus had ever considered as the great council of the nation, was composed of the most distinguished of the Romans; and distinction of every kind soon became criminal. The possession of wealth stimulated the diligence of the informers; rigid virtue implied a tacit censure of the irregularities of Commodus; important services implied a dangerous superiority of merit; and the friendship of the father always insured the aversion of the son. Suspicion was equivalent to proof; trial to condemnation. The execution of a considerable senator was attended with the death of all who might lament or revenge his fate, and when Commodus had once tasted human blood he became incapable of pity or remorse.

Of these innocent victims of tyranny none died more lamented than the two brothers of the Quintilian family, Maximus and Condianus, whose fraternal love has saved their names from oblivion and endeared their memory to posterity. Their studies and their occupations, their pursuits and their pleasures, were still the same. In the enjoyment of a great estate they never admitted the idea of a separate interest: some fragments are now extant of a treatise which they composed in common; and in every action of life it was observed that their two bodies were animated by one soul. The Antonines, who valued their virtues and delighted in their union, raised them, in the same year, to the consulship; and Marcus afterward intrusted to their joint care the civil administration of Greece, and a great military command, in which they obtained a signal victory over the Germans. The kind cruelty of Commodus united them in death.

The tyrant's rage, after having shed the noblest blood of the senate, at length recoiled on the principal instrument of his cruelty. While Commodus was immersed in blood and luxury, he devolved the detail of the public business on Perennis, a servile and ambitious minister, who had obtained his post by the murder of his predecessor, but who possessed a considerable share of vigor and ability. By acts of extortion and the forfeited estates of the nobles sacrificed to his avarice he had accumulated an immense treasure. The prætorian guards were under his immediate command; and his son, who already discovered a military genius, was at the head of the Illyrian legions. Perennis aspired to the empire; or what, in the eyes of Commodus, amounted to the same crime, he was capable of aspiring to it, had he not been prevented, surprised, and put to death.

The fall of a minister is a very trifling incident in the general history of the empire; but it was hastened by an extraordinary circumstance, which proved how much the nerves of discipline were already relaxed. The legions of Britain, discontented with the administration of Perennis, formed a deputation of fifteen hundred select men, with instructions to march to Rome and lay their complaints before the Emperor. These military petitioners, by their own determined behavior, by inflaming the divisions of the guards, by exaggerating the strength of the British army, and by alarming the fears of Commodus, exacted and obtained the minister's death, as the only redress of their grievances. This presumption of a distant army, and their discovery of the weakness of government, were a sure presage of the most dreadful convulsions.