That was the seventh anniversary of the battle of Actium. That's a good place to start, but many of the characters like Claudius, Caligula, Germanicus haven't been born yet.

We had started an interesting role play about the death of a young girl at Agrippina the younger's (mother of Nero, wife of Claudius) hand. It was in the time of Caligula's reign. This gets most of the major characters involved.