Slowman if you are reading:
Mandarin is not forced upon Han by Manchus. The real Manchrian language is very close to Mongolian and Korean, which is Altaic. Mandarin is a genre Northern Chinese language spoken in Beijing/Tianjian area. Standard Chinese is variation of Northern Chinese languages which is spoken in no where and every where.
Most Northern Chinese dialects are mostly mutually intelligeable. All Southern Chinese languages are not very mutually intelligeable to Northern ones and to each other.
The difference is that Southern Chinese languages are distinct and should be categorized into different languages, while the dialects of Northern Chinese language aren't that much different.
Funny how KMT had tried to do this before. In the end, local language grew even stronger. The forced uniformity makes me want to puke, and can only achieve the opposite.