I know this is a joke/meme, but I sincerely think of the Roman Empire a surprising amount of times. I find myself obsessing over how Roman citizens were living just as complex lives as we are today, or about Marcus Aurelius’ life and philosophy, or about how the Republic fell and became a totalitarian state.
I think on Rome fairly often, but it's usually more often on the republic.
I was thinking about this literally yesterday, on the nature of Octavian betraying the Republic, and how the Iulii and the Claudii simply kept themselves on power through the whole process. (Both gentes were already powerful in Republican times.) Or how some of the Claudii called themselves "Clodius" instead of "Claudius" for the sake of populism. ("See? I'm from the people! I even speak like a pleb!")
Even the state of politics dating back to the Grachi. Gradually becoming more violent and turbulent and Rome's reach and power grew. A society of adapters who could no longer adapt to the fast pace of change.