As I’ve commented before, films about ancient Rome always get the names wrong (or nearly always). Perhaps because it’s a TV show based on a novel drawn heavily from Roman sources, I, Claudius doesn’t butcher Roman naming conventions by just making up whatever nonsensical Roman-sounding names the screenwriter wants. So kudos to Robert Graves and Jack Pulman! But that doesn’t mean the show gets the names exactly right.
Several of the characters are not referred to properly. To refresh your memory, upper-class Roman male names have three components: the praenomen, the nomen, and the cognomen. The praenomen was a man’s private, personal name, like the Western ‘first’ name. It was used by his family and his closest friends in private, but was not generally used publicly. His nomen was his clan’s name, essentially the Western ‘last’ name, and was the normal way to refer to a man in public. The cognomen was used to distinguish that specific man from the various other men who might have his praenomen and nomen. It was often a nickname based on a significant feature of his body (Ahenobarbus means ‘bronze-beard’, for example), but it could also be a reference to a personality trait or something else. A man’s cognomen sometimes became so strongly associated with him that it became hereditary, so that Ahenobarbus’ descendants would have that cognomen without having bronze beards. The Romans also sometimes granted men an agnomen, a name that indicated a great accomplishment; Scipio was granted the agnomen Africanus after defeated Carthage in the Second Punic War. Unlike cognomens, agnomens rarely became hereditary.
Claudius was not the emperor’s praenomen; it was his nomen. But throughout the series, his family refers to him as Claudius. This would be like everyone in my family called me ‘Mr. Larsen’ throughout my life. His nomen was Tiberius, and that’s what his family called him. For example, Suetonius quotes several letters written between Augustus and Livia about the boy, and they consistently refer to him as Tiberius. However, it’s easy to see why the show does this. There’s already a Tiberius who’s an important character in the show, and Claudius is historically referred to by his nomen rather than his praenomen, so it would be confusing to viewers.
Several other characters are also referred to using names that it’s unlikely their families would have employed. Postumus was a traditional cognomen for men who were born after their father’s death. Marcus Agrippa Postumus would have been called Marcus, but the show already has a Marcus Agrippa and a Herod Agrippa, so clearly the show decided to call him by his cognomen so viewers wouldn’t be confused.

John Castle as Postumus
The character the show calls Germanicus (played by David Robb) was probably born Nero Claudius Drusus, but all three of those names are used by other characters. Scholars aren’t clear what his actual birth name was, because the sources consistently use his agnomen Germanicus. His father referred to as both Nero Claudius Drusus and Drusus Claudius Nero and in the show simply as Drusus (Ian Ogilvy) received that agnomen for his conquests in the Rhineland. The Julio-Claudians had a tendency to treat agnomens as hereditary, and so Drusus’ son wound up with it as an agnomen. The sources pretty consistently call him Germanicus so that’s how the show names him, even though that probably isn’t how his family called him.
Something similar happens with Claudius’ son Tiberius Claudius Caesar. When Claudius’ troops conquered Britain, he was accorded the agnomen Britannicus. He turned it down for himself and awarded it to his son instead. The show calls this boy Britannicus, whereas his family probably called him Tiberius, although given that that was his father’s praenomen as well, they might have called him Britannicus simply to distinguish him from his dad.
In a rather different vein, the emperor Caligula’s full name was Gaius Julius Caesar Augustus Germanicus. Caligula was actually an agnomen he picked up as a child. As a small child, he lived in his father Germanicus’ military camp, and Germanicus seems to have dressed him like a Roman soldier, including having child-sized military sandals, caligae, made for him. Caligula is a diminutive form of caliga, meaning literally ‘Little Boots’. It was a nickname the soldiers gave him, and as an adult, he despised it. In the series, everyone refers to him as Caligula. When he was a child, that’s plausible, but as an adult, it’s unlikely people called him that to his face, especially after he became emperor. But Caligula is how everyone thinks of him today so the show uses that. (I tend to think of him as Gaius Caligula.)
Probably the most egregious example of this happens with Castor (Kevin McNally), the son of Tiberius. His name was Drusus Julius Caesar. Castor was an agnomen he picked up in his early 20s when he got into an argument with someone and punched the name. The gods Castor and Pollux were associated with boxing, so Castor was a joking reference to that incident. But in the series, he’s called Castor even when he’s a young boy, long before he acquired the nickname. The obvious reason for this is that the show already has a Drusus.

Kevin McNally’s Castor
The show makes a pretty reasonable set of choices here. Roman naming practices were getting pretty confusing by the early Principate; the Julio-Claudians repeatedly changed their names and the use of agnomens got somewhat out of hand because they were trying to emphasize how militarily successful they were. They also wanted to shoe-horn in the fact that they were legally descended from Julius Caesar and Augustus, because they wanted to draw on the popularity of those two. And the practice of emperors adopting their successors caused name changes as well. If the show had tried to be historically accurate with names, the viewers would have been bewildered. The fact that several characters had the same praenomen would also have led to confusion. And Caligula and Claudius are known by those names and not their praenomens. So I think the show has good justification for fiddling around with the names of its characters.
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I agree — This is one of the cases where a show made reasonably good choices for picking the names it did (unlike, say, The Tudors creating characters out of whole cloth bec. too many “Marys” would be confusing). Reading thru the family names on WIkipedia is nuts. I can’t imagine how maddening it must be in the source material!
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Yeah, the Wikipedia pages are a bit headspinning when you try to track the names. The naming system sort of broke down, I think.
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There were only something like 14-20 praenomen in common use at that point, and some of them were only used by certain families. So it’s very easy to die of an overdose of Gaius.
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Yes. And it’s striking that the Romans never adopted Greek names as praenomens.
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I think it’s interesting how, with the emperors, starting with Constantine, you just stop seeing praenomens altogether. Constantine himself was Flavius Valerius Aurelius Constantinus Augustus….no praenomen at all, I don’t know how much of that was just that the use of praenomens were dropping out of fashion among the upper class, or the increase of Emperors that didn’t come from one of the old noble families, or what.
I mean,for instance, Theodosius claimed to be descended from Sextus Julius Caesar (The one who was the famous Caesar;s cousin, who fought with him in the Civil War and was killed by his own troops), but whether that’s true or not, or just a case of family tree polishing, who knows.
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It might be worth mentioning that in the book Claudius describes how he was called Tiberius (or perhaps Ti. Claudius) within the family in childhood. Until one day he has a conversation with a girl his own age (a Camilla) who comments that Claudius suits him better, as it means lame. Of course the TV series doesn’t have time for this, you’re right to cut them slack on the names.
When it comes to “Caligula”, the book is almost as bad as the show, only briefly describing how he got the name.
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Reading historical fiction has left me with an impression of how the praenomen, nomen and cognomen were used in everyday life that’s a little different from what you’ve described:
In Colleen McCullough’s Masters of Rome series, at the start (a generation or so after the Gracchi) characters address usually each other by praenomen and nomen e.g. Gaius Julius. By the last book (2nd Triumvirate) this usage is preserved only in very formal situations (such as speaking in the Senate). Over the course of a few generations it becomes more and more common to address friends by their cognomen only. In fact Caesar’s mother calls her son “Caesar” where she had called her husband “Gaius Julius”. Under this newer convention praenomina are occasionally used with cognomina to distinguish individuals who share both nomen and cognomen, e.g. when talking to Marcus Cicero and Quintus Cicero, you leave out the “Tullius”.
Do you know how accurate this is? Any idea where I could check a good secondary source?
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My understanding is that the praenomen is a private name only. Using an unrelated man’s oraenomen in public is insulting because it is a statement of social superiority–slaves and freedman can be addressed that way. So McCullough is wrong.
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Do you mean that the praenomen would never be used in public at all, even with the nomen or cognomen? If that’s so, do you have any idea how else they could distinguish brothers in public? Cousins can have “filius” and “nepos”. Maybe “major” and “minor” would work for brothers…
(McCullough never has characters addressed by just the praenomen without at least one of the other names.)
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In his letters Cicero calls Caesar “Gaius Caesar”. Cicero was obviously a contemporary who knew Caesar and other Romans are called this way by his as well. Roman mhistorians call Caesar just that as he does when he writing his own military accounts in the third person. He is never called Gaius Julius or Julius Caesar, Gaius Julius Caesar is used occasionally but very rarely. But this is in writing so it’s hard to tell what people called themselves when informally addressing one another. We just don’t know for sure since spoken and written language is different. But in my understanding you don’t use just prenomen unless you are very close with someone.
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That’s an interesting fact. Cicero was, of course, a ‘new man’ and not at all the social equal of a Julian. But of course, Cicero was an optimate and thus across the political divide from Caesar. It makes me wonder if he was deliberately tweaking Caesar by showing a greater familiarity than he really ought to have done.
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Should we read anything into the fact that Tiberius and Gaius were known by those names rather than as “Caesar Claudianus” and, I don’t know, maybe “Caesar Germanicus”? (At first glance it looks like a shift towards the practices of modern European monarchs but that’s obviously an anachronism.)
And then Claudius and Nero are known by nomen and cognomen.
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That I can’t really explain. I’m not sure how those names were settled on.
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As you well know, we call you Dr. Larsen the Younger. We’re not barbarians.
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“They also wanted to shoe-horn in the fact that they were legally descended from Julius Caesar and Augustus, because they wanted to draw on the popularity of those two emperors.”
Your wording makes it seem you believe Julius Caesar was an emperor? But it’s probably just a mistake.
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You’re right that my wording there is sloppy. I’ll tweak it.
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I could not respond to the comment you left under mine above and I do not know if you can see if I respond to myslef.
I did not mean that Cicero mostly used Gaius Caesar, Caesar is much more common. For other example he usually uses Pompey but uses Gnaeus Pompey occasionally as well. So he did use this system for plenty of other people, Caesar was just an example I used. He used the common Roman abreavitions such as P. Clodius as well. I meant that using pranomen was not unusual if paired with the cognomen so its not just private. It would have been a nightmare to separate with family members otherwise. What would you for example call Caesar’s cousin Lucius Julius Caesar if you can’t call him Lucius Caesar like he was? This is why men neened the prenomen, to separate for political reasons. Women were fine with just the feminen version of the nomen since they were rarely referenced to. But the prenomen don’t just pop up for differenting relatives but quite casually with Cicero’s writing.
And while Cicero was a novus homo he was an ex-consul and also knew Caesar for a long time and well. Caesar even asked him for the triumvirate (which would have been a tetrarchy had he joined.
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Oh and I forgot to say I remembered the roman historians sometimes called Caesar the divine Julius but maybe they did that because he was not an emperor so they wanted to avoid Caesar.
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The distinction between GJC and LJC publicly would probably be addressed with a cognomen or agnomen. That is why those names evolved in the first place.
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