Confucianism in particular raised fierce opposition to Buddhism in early history, principally because it perceived Buddhism to be a nihilistic worldview, with a negative impact on society at large. "The Neo-Confucianists had therefore to attack Buddhist cosmological views by affirming, in the firstplace, the reality and concreteness of the universe and of man."
Before Prince Shotoku made Buddhism the national religion of Japan, many opposed the integration of Buddhism into Japan. Once this forced integration occurred, Japan synchronized Buddhism with its native religion Shinto, resulting in a unique sect of Buddhism existing only on the East Asian Island.
In the Japanese religion of Shinto, the long coexistence of Buddhism and Shintoism resulted in the merging of Shintoism and Buddhism. Gods in Shintoism were given a position similar to that of Hindu gods in Buddhism. Moreover, because the Buddha Vairochana's symbol was the sun, many equated Amaterasu, the sun goddess, as his previous bodhisattva reincarnation. The later Tokugawa Shogunate era saw a revival of Shinto, and some Shinto scholars began to argue that Buddhas were previous incarnations of Shinto gods, reversing the traditional positions of the two religions. Shinto and Buddhism were officially separated during the Meiji Restoration and the brief, but socially transformative rise of State Shinto followed. In post-war modern Japan, most families count themselves as being of both religions, despite the idea of "official separation".
As time went on, the Japanese became more and more accustomed to including both the kami and Buddhist ideas in their spiritual lives. Philosophers put forward the idea that the kami were "transformations of the Buddha manifested in Japan to save all sentient beings".
The relationships between Taoism and Buddhism are complex, as they influenced each other in many ways while often competing for influence. Taoism in its early form was a mixture of early mythology, folk religion, and Taoist philosophy. The arrival of Buddhism forced Taoism to renew and restructure itself into a more organized religion, while addressing similar existential questions raised by Buddhism. Early Buddhism was sometimes seen as a kind of foreign relative of Taoism and its scriptures were often translated into Chinese with Taoist vocabulary. Ch'an Buddhism in particular holds many beliefs in common with philosophical Taoism.
Daoist (Taoist) simplicity stimulated Chan's abandonment of Buddhist theory and was accompanied by another traditional Daoist feature—the emphasis on total absorption in practice of a highly cultivated skill.