[Cincinatus]

Colleen McCullough (whose Roman Republic novels are masterpieces of historical research) claims that the real Spartacus was not "Thracian" but that honorific indicated the type of gladiator he was (or style of fighting -- Thracian gladiators were heavily armored, versus the lighter armed "Gallic" or "Celtic" gladiator.) She further claims that the real Spartacus was a Roman centurion, sold into gladiatorial service after a mutiny, thus explaining his apparent tactical genius against the legions sent against him.

[Destro]

The name is a giveaway to his origins - Spartacus. This article claims he may have been a Greek auxiliary to the Romans rather than a centurion. I think auxiliary makes more sense. It could have been an inside joke for the Romans too, a "Thracian" fighting as a Thracian. I could imagine the fight bill!

The gladiator games had a religious significance to them. They were a form of human sacrifice (even if no one was killed) and the fighting styles of the gladiators were highly stylized to act out some sort of quasi-religous cosmic play.