Good question. I’m curious myself.
If you like historical fiction, read The Memoirs of Cleopatra. Interesting.
I can heartily recommend a whole series of novels by Colleen McCullough. They cover the whole decline and fall of the Republic from Marius to Cleopatra, Antony and Octavian.
Extremely well written and generally quite accurate, although she seems to have gotten the idea from somewhere that Caesar’s legions could routinely cover 40 miles day after day, building fortified camps each evening. I don’t think so.