The principal culture of the East Asian cultural sphere is Chinese culture, with Japanese culture, Korean culture and Vietnamese culture lying on the peripheries. In particular, Japan, Korea, and Vietnam were all at one point prominent tributary states of China following extensive prior interactions. Shared features of countries within the East Asian cultural sphere include their philosophies, beliefs, religions, political structures, social institutions, laws, rituals, military doctrines, medicine, science, literature, art, cuisine, architecture and so on. Common belief systems throughout the region include Confucianism, Buddhism and Taoism.