The government of planet 892-IV, a parallel Rome that never fell and that combined a twentieth-century industrial society with slavery, proconsuls and televised gladiatorial combat.
The empire of 892-IV is a striking case of parallel planetary development: a Rome that endured into an age of motor cars, machine guns and television. Slavery has become a settled institution with pensions and medical care, and gladiators fight to the death in a studio for a broadcast audience.
The state appears in Bread and Circuses. Its First Citizen, Merikus, is really R. M. Merik, captain of the lost survey ship Beagle, who had his own crew sent to the arena. Real power rests with the proconsul Claudius Marcus, who tries to force Kirk to do the same.
The empire is troubled by runaway slaves who preach peace and brotherhood. Uhura realises at the end that these worshippers follow not the sun but the Son of God.