Creating a new campaign

Is it possible to create a campaign starting around the year 110 B.C., to play as the Romans, with all the provinces of the Roman empire as it was at that point in place, and with the Marian reforms already implemented? If so, how can one go about creating this campaign?

Thank you in advance for your answers!

Well, I'm not sure how but I can tell you it will take a lot of work from eliminating factions, adjusting the script, balancing all the factions, etc.

Take a look at EB\Data\world\maps\campaign\imperial_campaign\descr_strat.txt. That's where the campaign is laid out.