but you are misunderstanding the connotation. The aim was not to seek a separate state for the "Wu people" based on "Wu language" or "Wu culture". It was a new dynasty name, and like most Chinese rebellions, aimed to unite ALL OF CHINA under the banner of Wu.
I think you're misunderstanding my argument here, and maybe I didn't make it clearly. With two cores, "Being Wu" does not mean that you're giving up a claim to China, simply that you can sustain an independent state of Wu for some time if the tides of war do not deliver China into your hands. "All under Heaven" can serve as a constant source of casi belli that prevent this state of affairs from going on too long.
The founder of the Ming dynasty, Zhu Yuanzhang, proclaimed himself as the "King of Wu" in 1364 AD before establishing the Ming Dynasty in 1368 AD. Using your logic, Zhu would've been happy to stay as the "King of Wu" and have a state based solely in Jiangsu/Zhejiang, centered around "Wu culture" and "Wu language".
No -- few monarchs in our period would ignore a claim to someone else's territory, if they had the mans to press it. If the Duke of Brittany has a claim to the throne of France, he will conquer it -- if he can -- and then crown himself King of France.
I'm not actually familiar with the chain of events, but if Zhu Yuanzhang set himself up as King of Wu when he ruled a specific territory -- a region known as Wu, where they speak Wu, and where at least three pre-existing states have been called Wu -- then that suggests an independent political identity there
that coexists with the larger political identity of China.
Another interesting possible example of "upgrading" your dynasty name as you set your sights higher: the 10 Kingdoms kingdom in Guangdong was founded as Great Yue. But one year in, the founder (Liu Yan) renamed it Great Han. This would suggest that you could choose to emphasize a regional or pan-Chinese identity, depending on how strong your hand was, right?
(paragraph taken out after reading more on the topic)
the vast majority of large scale and organized "rebellions" (i.e. not aimless peasants or cults, but led by generals with an army) in Imperial China aimed to replace the ruling dynasty with a new one, not to establish a provincial kingdom or dukedom somewhere.
There's no such thing as an aimless peasant rebellion, merely a rebellion whose aim is unknown to us because it's not written down in the imperial annals.
A local Chinese potentate isn't just pitching himself to scholars steeped in the "All under Heaven" concept. He's also pitching to peasant rebels who've probably formed the bulk of his forces. Their concerns may be
much more local. Most rebellions in Chinese history may have kept unification as an ultimate, theoretical aim, but some did not try very hard to push it.
Societies cannot be understood purely through their ideologies. You can't explain the history of medieval Europe only by reading the Bible. The Ten Kingdoms lasted for one to two generations and corresponded fairly closely to linguistic regions. That suggests that, in practice, a region-based polity had some stability, even if the rulers and scholars thought of it as a half-way house to the whole deal.
As for the linguistic-political correlation, it doesn't mean that peasant rebels are out there shouting "Min for the Min!" It could be something as simple, and subtle, as the peasants deciding that if they need to cut a deal with a particular warlord, they'll choose the one who talks like them.
By all means have separatist factions that have a chance to rebel - but don't for one moment claim it's because of "cultural differences". Each such faction should have cores on all of China to model the fact that these are not separatist rebels but rebels who seek to overthrow the ruling dynasty.
I think we agree here on the mechanics -- but the borders of the Ten Kingdoms line up pretty closely with linguistic boundaries, so I'd be pretty surprised if cultural differences don't play a part. They are not the sole variable in any rebellion, but complex social phenomenon (ie, a rebellion) has a single cause.
And again, if you have a 14th century state of Wu in the site of the 10th and 4th century states of Wu in an area known as Wu where they speak Wu, I think that's pretty strong evidence of a regional political identity -- regardless of whether the annalists of the next dynasty choose to mention that -- and that there is some historical memory of the 10th century Wu state as late as the 14th century.
But yes, the ambitions of the ruler and the local intelligentsia would certainly extend beyond.
Yuan Chonghuan, the literati-commander who defeated Nurhaci in 1626, was from Guangdong, the southernmost province of China (
http://en.wikipedia.org/wiki/Yuan_Chonghuan). To claim that he was somehow less loyal or dodged taxes or had higher chance to rebel because he was "yue" rather than "han" is just preposterous.
Bretons served as loyal Constables of France. This does not mean that there was no Breton regional political identity.
People are complicated and political behavior is one of the most complicated and counter-intuitive things about them. You cannot reduce their behavior to a single variable. But that does not mean that variable does not exist.
Let's take a group of generals, all from the same region. They participate in a national military, but they gravitate toward each other and form a "clique." They are disgruntled for many reasons, but they are most comfortable with people from their own backgrounds. When they rebel, they start in their homelands because they're better able to stir up their troops better when they talk in colloquial. Such a thing is possible in Chinese history, right? This is regional identity playing a major role, but not being the sole variable or a stated motivation for rebellion.
But... Yuan Chonghuan does illustrate one thing about China that maybe should make a difference: no single linguistic region monopolized the bureaucracy. You would know better than I about this, but my guess would be the following. A northern peasant is as likely to be angered by a southern bureaucrat's decision as a southern peasant is likely to be angered by a northerner.
So, maybe in a Celestial Empire (the EU government form) you can have regional rebels, they're just not necessarily any more likely in one region (so long as that has a core) than another. Unless the northerners did dominate the bureaucracy, in which case there probably should be penalty. Linguistic differences between administrating scholar and peasant would likely be an extra bit of friction, if the peasant already has a grievance.