Cassius Dio, LXXII.15.2-6:

He actually ordered that Rome itself should be called Commodiana, the legions Commodian, and the day on which these measures were voted Commodiana. Upon himself he bestowed, in addition to a great many other names, that of Hercules. Rome he styled the "Immortal, Fortunate Colony of the Whole Earth"; for he wished it to be regarded as a settlement of his own. In his honour a gold statue was erected of a thousand pounds weight, representing him together with a bull and a cow. Finally, all the months were named after him, so that they were enumerated as follows: Amazonius, Invictus, Felix, Pius,⁠ Lucius, Ælius, Aurelius, Commodus, Augustus, Herculeus, Romanus, Exsuperatorius.

For he himself assumed these several titles at different times, but "Amazonius" and "Exsuperatorius" he applied constantly to himself, to indicate that in every respect he surpassed absolutely all mankind superlatively; so superlatively mad had the abandoned wretch become. And to the senate he would send messages couched in these terms: "The Emperor Caesar Lucius Ælius Aurelius Commodus Augustus Pius Felix Sarmaticus Germanicus Maximus Britannicus, Pacifier of the Whole Earth, Invincible, the Roman Hercules, Pontifex Maximus, Holder of the Tribunician Authority for the eighteenth time, Imperator for the eighth time, Consul for the seventh time, Father of his Country, to consuls, praetors, tribunes, and the fortunate Commodian senate, Greeting." Vast numbers of statues were erected representing him in the garb of Hercules. And it was voted that his age should be named the "Golden Age," and that this should be recorded in all the records without exception.