I was once in a debate with a fairly radical Muslim who wanted the Caliphate to come back. We got to talking about territory and he said the same thing. This of course included Spain and a good chunk of Eastern Europe.
Then of course there's a bit of Chinese history which is no doubt behind some battles China and India have fought:
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China thinking that they are entitled to any territory that was once theirs is a recipe for war.
And, oh yes, China invading and taking Tibet over is another example of that principle. As is the warmongering bellicosity over Taiwan.
I have no confidence that they won't "discover" some ancient claim to even more than they held in the Qing dynasty.