actually, they are both real people... both characters based on real people
https://en.wikipedia.org/wiki/Titus_Pullo
https://en.wikipedia.org/wiki/Lucius_Vorenus
from your own link...
Fictional depictions[edit]
- Titus Pullo is one of the principal characters in the HBO/BBC/RAI original television series Rome. Unlike the historical Pullo, the fictional Pullo is a member of the 13th Legion, (Legio XIII Gemina), an ally of Caesar, and particularly of Octavian.