I am amazed as to the type of unnecessary complexity that some forummers here give.
To simplify the answer.
Yes, the Han ethnicity refer to the majority ethnic group ruled under the Han dynasty.
But the southerners usually refer to themselves as the Tang dynasty people rather than the Han dynasty.
Tang dynasty was grander and larger than the Han dynasty.
Southerners still refer to china as '唐山' ie. land of the tang.
It has nothing to do with the 3 kingdoms which was just a country broken up into 3 pieces after the Han dynasty.
The Chinese 3 Kingdoms period was after the fact. The kingdoms were avoiding being considered separate ethnic groups because they had linked themselves to a Han dynasty identity. Wei Wu and Shu are not divided along the previous lines of the warring states period. The lines became blurred and expanded to new frontiers. It's just like Persians call themselves a group but were originally Babylonians Assyrians Canaanites etc. Qin Han Wei Zhao Chu Qi Yan were the same situation. I also mention the 3 Kingdoms because it differes from 3 Kingdoms in Korea. Korea 3 Kingdoms period was really their warring states period and their north and south Korea today is really their 3 Kingdoms period. it would be preposterous to conclude that everyone that was under control of the Han dynasty was actually politically Han let alone ethnically Han in the supraethnic sense. Goguryeo was such a case and when the Han dynasty ended those people that had ties to Lelang commandery had legitimate reason to self determine for their people. Goguryeans would have had no ambition for the Han dynasty because they obviously had in mind something different in trying to create a secondary state in the area of modern day Korea. Now if all these Chinese "Han" could move themselves up in mentality to understand that Han is not just derived from the Yellow river of Shanxi everything would be settled.
Calling oneself a Tang person is not inaccurate although using Han is somehow more beloved due to the writing that emerged from the period as well as Confucianism. The north was occupied by nomadic conquerors which continually reshaped the politics of China so that in later periods, upheaval and splittism continued to exist because newcomers were trying to form secondary states like Xi Xia and Liao. This was all completely remade over by the Tang people and then by the Song people. However the Mongolians came and tried to reset everything into the Mongolian scheme which didn't work out so well so now maybe the Ming title is up for use or the Qing title China.
Edited by mohistManiac, 14 September 2012 - 01:24 PM.