Tang ruled Shang, one of the many kingdoms under the suzerainty of the Xia dynasty, for 17 years. During Jie's reign, Shang grew in power, initially at the expense of Xia's other vassals. He was able to win many supporters from as many as 40 smaller kingdoms. Tang recognized that Jie mistreated his people and used this to convince others. In one speech, Tang said that creating chaos was not something he wanted, but given the terror of Jie, he had to follow the Mandate of Heaven and use this opportunity to overthrow Xia. As an advantage he pointed out that even Jie's own military generals would not obey his orders.