The History of the Roman Empire at the time of the crisis of the 3rd century is not known well. The historicity of the Battle of Naissus is controversial. One of the most important arguments put forward in its favour is the assumption of the title Gothicus Maximus by Claudius II. It is the earliest attestation of this title in the Roman propaganda. In my article I analyse the assumption new cognomina ex virtute in the 3rd and 4th centuries (Carpicus Maximus, Gothicus Maximus, Alammanicus Maximus, Franciscus Maximus, Persicus Maximus). Emperors did not need a great undeniable victory to introduce new cognomina ex virtute. The assumption of a new title served to express the significante of the cognomen given to the ruler, not the scale of his success. The title Gothicus Maximus cannot be regarded as a proof of a spectacular success of Claudius II at Naissus, but only of his victory over the Gothi.