Some of the earliest histories of Western civilization feature an idealized past that was better than whatever time the historian lived in, most famously Hesiod and perhaps arguably Jewish authors of the Tanakh, who pined for the mostly righteous kingdom of Judea of yore. Piled onto these traditions, we have the more tangible fall(s) of the Roman Empire, Western and Eastern. Hardly a European-civ state didn’t look back to Rome as a sadly-gone model to be emulated—and hopefully recreated. Consider Washington D.C. and how far-removed that is from its inspiration!
But what about China? Japan? Korea? Do any of these venerable civilizations have any similar cultural recollections of a formerly great civilization? If so, have they tried to emulate or recreate it?
Whilst you are waiting for a proper response, you can read some earlier threads (here and here) on Romance of the Three Kingdoms, both written by u/Dongzhou3kingdoms, which mention that there was a nostalgia for the Han dynasty ever afterwards. There is also this answer by u/DeSoulis where current-day China's nostalgia for history before the "Century of humiliation" is discussed.