After Wu's reign, Han forces continued to prevail against the Xiongnu. The Xiongnu leader Huhanye Chanyu (呼韓邪) (r. 58–31 BC) finally submitted to Han as a tributary vassal in 51 BC. His rival claimant to the throne, Zhizhi Chanyu (r. 56–36 BC), was killed by Chen Tang and Gan Yanshou (甘延壽/甘延寿) at the Battle of Zhizhi, in modern Taraz, Kazakhstan.