Eisenhart
Warlord
Hmm. I wonder if that far in the future they mastered cloning + brain transplant. (With the rationalization that it's horribly expensive and/or kept Top Secret from the worker drones.) Every 10 years Fearless Leader transfers his brain to a fresh clone. To the outside world he looks immortal. (Always good for PR.)
That would make this the first Civ that has an explanation for why a faction/civilization has the same ONE leader being in office literally for centuries.
This reminds me of flash-cloning in the EvE universe. Except you have multiple clones alive in one time.
An alternative would be Ghost in the Shell-style cyberbrains, then just copy the cyberbrain or some ghost to another brain / body.