I'm still very weak on my Chinese history, but it was the turning-inward of the Ming dynasty (15th century), not the Mongol invasions, which precipitated the halt.
Also (as already mentioned in this thread), the asset-sheltering tendency of established power groups, halting the emergence of potential rivals, as Bernhard Stern documents in other (non-Chinese) instances.
Also (as already mentioned in this thread), the asset-sheltering tendency of established power groups, halting the emergence of potential rivals, as Bernhard Stern documents in other (non-Chinese) instances.