Vietnamese inscription in Chinese characters: Thien Duc Thong Bao / Two characters in grass script: Van Tue ("10000 years"). 24.5mm, 3.31 grams. KM #138 (C39.1).
The name of Tayson (Tây Sơn) is used in various ways to refer to the period of peasant rebellions and decentralized dynasties established between the end of the figurehead Later Lê dynasty and beginning of the Nguyễn dynasties in the history of Vietnam between 1770 and 1802. Some academics refer to this period as the "Tây Sơn uprising." The name is used to refer to the leaders of this revolt (the Tây Sơn brothers), their uprising (the Tây Sơn Uprising) or their rule (the Tây Sơn Dynasty or Nguyễn Tây Sơn Dynasty). The Tây Sơn brothers styled themselves as champions of the people. They won some battles against the Nguyễn army units sent to crush their rebellion. The Tây Sơn had a great deal of popular support, not only from the poor farmers, but from some of the indigenous highland tribes. The leader of the three brothers, Nguyễn Huệ, was also a very skilled military leader. He declared himself an Emperor in 1778 under the title of Thai Duc.