The Historical "Yueh"
The southeastern coastal inhabitants were known to the Chinese as the Yueh barbarians. The name was extended southward as the Chinese expanded their empire. These Yueh people were noted for their skills in navigation and their savagery in battle; the population of the early state of Yueh (5th-4th centuries B.C.) centered in the Lower Yangzi practiced wet rice cultivation and were engaged in trade along the coast. Modern ethnographic and linguistic researches point to an Austroasiatic linguistic affiliation for these peoples. The Vietnamese retain the name "Yueh" and the Cantonese are also still called "Yuet" and derive in part from the aboriginal population.
The Yueh, in later texts referred to as the "Hundred Yueh", were certainly a diverse population, and may have included different language families and markedly different customs. The Tai-speaking Chuang of Guangsi province today have oral traditions of earlier occupation of coastal areas, and may have been included in the Yueh. Similarly, the Kedai-speaking Li tribes of Hainan Island are almost certainly descended from the Yueh.
A process of gradual though erratic cultural assimilation of the Yueh began after the Ch'in - early Han conquest, and by the end Han had brought a large number of the Yueh people into the sphere of Chinese culture. Han historical texts provide ample evidence of the acceptance of Yueh chiefs and high ranking individuals into the Han administrative system, even into the army itself.
The Han chamber tomb mentioned above may represent the presence of a Han official in the area of northern Kowloon, but it is equally possible that it represents a sinicized Yueh chieftain with Han patronage. However, there are few Han sites in the territory, and the implication is clearly that the large population suggested by number and richness of Bronze Age sites had dispersed.
By the Six Dynasties era, the local population seems to have revived, and evidence of lime kilns dating from the 3rd to the 9th centuries A.D. are found on most of the beach sites. These people were almost certainly partly assimilated Yueh -- the ancestors of the Cantonese.
[url-http://www.hkarch.org/en_news.html]Hong Kong Archaeological Society[/url]
That much for Hong Kong and south eastern Chinese being Han Chinese, taking the statistics of 92% of China are Hans!