American Tract Society Bible Dictionary
Originally the surname of the Julian family at Rome. After being dignified in the person of Julias Caesar, it became the usual appellation of those of his family who ascended the throne. The last of these was Nero, but the name was still retained by his successors as a sort of title belonging to the imperial dignity. The emperors alluded to by this title in the New Testament, are Augustus, Luke 2:1; Tiberius, Luke 3:1 20:22; Claudius, Acts 11:28; and Nero, Acts 25:8 Philippians 4:22 . Caligula, who succeeded Tiberius, is not mentioned.
These files are public domain and are a derivative of the topics are from American Tract Society Bible Dictionary published in 1859.
Rand, W. W. Entry for 'Caesar'. American Tract Society Bible Dictionary. https://www.studylight.org/dictionaries/eng/ats/c/caesar.html. 1859.