Decline & Fall, chapter 41

According to the testament of the founder, the African kingdom had lineally descended to Hilderic, the eldest of the Vandal princes. A mild disposition inclined the son of a tyrant, the grandson of a conqueror, to prefer the counsels of clemency and peace; and his accession was marked by the salutary edict, which restored two hundred bishops to their churches, and allowed the free profession of the Athanasian creed. But the Catholics accepted, with cold and transient gratitude, a favour so inadequate to their pretensions, and the virtues of Hilderic offended the prejudices of his countrymen. The Arian clergy presumed to insinuate that he had renounced the faith, and the soldiers more loudly complained that he had degenerated from the courage, of his ancestors. His ambassadors were suspected of a secret and disgraceful negotiation in the Byzantine court; and his general, the Achilles, as he was named, of the Vandals, lost a battle against the naked and disorderly Moors. The public discontent was exasperated by Gelimer, whose age, descent, and military fame, gave him an apparent title to the succession: he assumed, with the consent of the nation, the reins of government; and his unfortunate sovereign sunk without a struggle from the throne to a dungeon, where he was strictly guarded with a faithful counsellor, and his unpopular nephew the Achilles of the Vandals. But the indulgence which Hilderic had shown to his Catholic subjects had powerfully recommended him to the favour of Justinian, who, for the benefit of his own sect, could acknowledge the use and justice of religious toleration; their alliance, while the nephew of Justin remained in a private station, was cemented by the mutual exchange of gifts and letters; and the emperor Justinian asserted the cause of royalty and friendship. In two successive embassies, he admonished the usurper to repent of his treason, or to abstain, at least, from any further violence which might provoke the displeasure of God and of the Romans; to reverence the laws of kindred and succession, and to suffer an infirm old man peaceably to end his days, either on the throne of Carthage or in the palace of Constantinople. The passions, or even the prudence, of Gelimer compelled him to reject these requests, which were urged in the haughty tone of menace and command; and he justified his ambition in a language rarely spoken in the Byzantine court, by alleging the right of a free people to remove or punish their chief magistrate, who had failed in the execution of the kingly office. After this fruitless expostulation, the captive monarch was more rigorously treated, his nephew was deprived of his eyes, and the cruel Vandal, confident in his strength and distance, derided the vain threats and slow preparations of the emperor of the East. Justinian resolved to deliver or revenge his friend, Gelimer to maintain his usurpation; and the war was preceded, according to the practice of civilized nations, by the most solemn protestations, that each party was sincerely desirous of peace.

--Gibbon

... Regardless of his historical accuracy, Gibbon must be read for his rhetoric.