Answer:
Gladiators would have only fitted in the colonial and Pre-Civil War South. In the modern era, they would not fit at all.
This is because gladiators were slaves, who fought battles, often to the dead, against other gladiators, other soldiers, and even wild animals, for the amusement of the Roman Society.
After the Civil War, Gladiators simply do not fit into the culture of the United States and its democratic setting, and the reason is that slavery is prohibited in the United States.