	In 47, an opportunity arose with regard to Xiongnu. Xiongnu had a succession dispute, pitting the current chanyu, Punu (蒲奴) against his cousin Bi (比), the son of a former chanyu. In 48, Bi also claimed the title of chanyu, and submitted to Emperor Guangwu's authority. Punu also submitted, in response, and the divided Xiongnu stopped waging war against Han.