David M. Robinson contends that various edicts and laws issued by the Hongwu Emperor, founder of the Ming dynasty, seem to reject the Mongol influence in China with the banning of Mongolian marriage and burial practices, clothing, speech and even music. However, Robinson highlights how this rhetoric contradicts the Hongwu Emperor's continuation of Yuan institutions such as the hereditary garrison system and occupations. He initiated campaigns to conquer areas not previously controlled by native Chinese dynasties, including territories in Yunnan, Liaodong (Manchuria), and Mongolia. He continued to recruit Mongols into the military and maintained the Yuan-era tradition of bringing Korean concubines and eunuchs into the imperial palace. Robinson claims that the Ming dynasty "was in many ways a true successor" to the Yuan, as the Ming emperors sought to legitimize their rule through the Yuan legacy, especially since the rival Northern Yuan Dynasty continued to exist. The Yongle Emperor was far more explicit in invoking a comparison between his rule and that of Kublai Khan, as reflected in his very active foreign policy, projection of Ming Chinese power abroad and expansionist military campaigns. Following the 1449 Tumu Crisis, the Ming government actively discouraged further immigration of Mongol peoples (favoring occasional relocation policies for those who already lived in China). Mongols continued to serve as Ming military officers even after Mongol involvement in the failed 1461 Rebellion of Cao Qin, yet their numbers began to decline as hereditary officers in general were gradually replaced by men of more humble origins.