Yunnan,with varied ethnic groups and diverse cultures,lies in the border area of Southwest of China. Before the reign of Emperor WU,western Han Dynasty,the social development in Yunnan was quite imbalanced and was in different historical stages varied from the society of primitive tribe to that of slavery. After Emperor WU,Yunnan became a part of Han Dynasty. Till Eastern Han Dynasty,the majority of ethnic groups mixed together with Han nationality and entered gradually into the feudal society. Their cultures also witnessed the development from Bronze Age to Iron Age. This article aims at illustrating the great impact that the unification of Southwest area has played on the economic and social progress.
