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OPTIMVS. - This laudatory cognomen, first conferred on Trajan, was regarded by the Roman people as exclusively suitable to that Emperor, insomuch that after him (according to Pliny) it was a solemn custom in public acclamations thus to address each succeeding Augustus; "May you be better than Trajan:" (Sis melior Trajano). We learn from coins that Trajan did not accept this, by him most highly prized title of Optimus before his sixth consulate. There are extant some coins of Hadrian, who was adopted by Trajan and succeeded him in the empire, on which not only the name Trajanus, but that of Optimus is retained. - viz., IMP. CAES. TRAIAN. HADRIANVS. OPT. AVG. GER. DAC. - The appellation of Optimus conjoined to Maximus has already been noticed as occurring on a coin of Commodus. - And the same title appears on a consecration medal of Claudius Gothicus: DIVO CLAVDIO OPT. or OPTIMO.
Optimus Princeps. Patin in his work on Imperial coins (p455) remarks that not only Trajan, Antonine, Aurelius, and other good Emperors were honoured with this high compliment, but it is mendaciously applied (amongst others undeserving of it) to Sept. Severus. whose conduct, at least during the first years of his reign, was atrociously cruel and inhumanly vindictive. Nay even the Thracian Maximinus was so styled by the Senatus Populusque Romanus, at the very worst period of his bad reign, and at a time when he was not in Rome. The most probable supposition is that this barbarian was so called by his own creatures (terming themselves a Senate) out of sheer adulation.