This is something that has riddled me for some time. For a litterary project I'm in great need to come up with diversity of roman names. Slaves aren't a problem but I think the plebs and tha patricians very well might be. We take a famous romans patrician as an example.
Gajus Julius Caesar
Gajus is his first name, nothing speciell with that, could be anyone of the very few first names avalible.
Julius, he is of the family Julius, gens Julia.
But Caesar? As I have understod, that name signifies which branch of the family Julius he stemes from. Is this right? And if so, why couldn't he just as well be called Gajus Caesar Julius? Is the fathers or the mothers blodline the predominant one, and has that something to do with this convention?
And now he marries a woman from the family Cornelius, what would their boy or girl be named? I don't understand the logic behind this. It's common for a boy to take his fathers name, that happens but not allways.
And the plebs; do they generallt only have two names, like Lucius Priscus for instance? Or do the same mechanism apply to them to?
EDIT: Another thing is just a coincidence that the "ius"-name is placed in the middle. Marcus Porcius Cato. Marcus Tullius Cicero, Gajus Julius Caesar and so on.