And why do (most - or all?) written references use Gaius and yet the inscriptions on his coins use C (Caius) CAESAR? The die engravers could certainly render G as can be seen, for instance, in GERMANICVS
Some Roman Emperors had nicknames. For instance we have Elagabalus or Helio Gabalus (worshiper of the Sun) though his imperial name was Marcus Antoninus. The same reason applies to Caracalla, but I don't know here if this nickname is related to the murder of his brother. I searched in many references but without a clue. There are also other reasons for the names applied to the Emperors, possibly by Historians, I modestly think, who wanted to avoid confusion. Maybe that's why we have Gallerius instead of Maximian, or Maximinus Thrax I, or Maximinus Daia II, etc.. We can also cite Empress Eudoxia, Eudocia, Licinia...
+1 on that. Augustus: “Quintili Vare, legiones redde!” Did anybody address the emperor like that in direct speech? Plinius the Younger called Trajan ‘domine’ in his letters.
I think Pliny addresses him that way because he was still a subject of the emperor, even though he was a provincial governor.
I was taught in school overr 50 years ago: Both Caligula and Caracalla were names given by the soldiers when the boys were young and with dad on the fronts. Neither was appreciated and neither would have been said to their faces. Praenomena (Gaius, Marcus) were used alone to address the person by family and friends but others would have used a family name. A generation before me many people were known by their last name rather than the first. I have heard 'Smith' alone but more often it was preceded by a title like Mister or Sergeant. Today, many people under about 40 call me 'Mr. Doug' which was not heard when I was younger. I can not swear that the correct answer to this under Caligula would have been the same under Aurelian. Time change. The last time I saw my grandmother before she died in her 90's (in the mid 1970's), she did not remember her husband's first name. He died in 1944. She always called him Mr. Smith. His children and friends knew him by his middle name but called him 'Dad' or 'Smitty'. I found out much later that his legal first name was only used on legal documents. It was his way. I believe at least some of the names from cultures that place the family name first consider it appropriate to use a family name when addressing someone and not use the third name unless they are quite close. Is this correct? I am sure someone has written a book on this subject but I have not seen it.
We have Cicero's personal correspondence with "Atticus". We'd have to look at the original Latin to see how he addressed a close friend.
Anyone ever see "Up Pompeii" from old British TV? A couple of the characters were Ammonia and Erotica.
