Tribute system is an important frame in all feudalism period of China based on its ritual and value system.There are a lot of minority nationalities in southwest and south areas which were called Man or Yi who began to pay tribute to Emperor in quite early period.In the Tang Dynasty,the state was very strong and the minority nationalities followed the emperor.At its highest period,there were over seventy minorities paid tribute to the emperors.The minority nationalities sent pearls and gold and expensive go...