The Ming dynasty of China presided over another period of Pax Sinica.[26] This period saw the formal institutionalization of the Chinese tributary system, illustrating the great political power of China at the time.[27] The seven maritime expeditions led by Zheng He projected the imperial power of the Ming dynasty across Southeast Asia, South Asia, the Middle East, and East Africa.[28] During this period, China also exerted a great amount of influence on the culture and politics of Korea.[29][30]