I suspect the China issue was a carve out in the comment you replied too. Since they were referring to the west. As for Rome, it was never a Nation in the mode

I suspect the China issue was a carve out in the comment you replied too. Since they were referring to the west. As for Rome, it was never a Nation in the modern sense. It started as a city state and became an empire. My understanding is that nation states (where the rule and the border were defined nationality of the population) were born as a reaction against empire. Starting with the French Revolution, where the desire for the French to be ruled by French in France was new concept.