Final answer:
China had a significant impact on the culture and literature of early classical Japan, influencing their adoption of Chinese writing systems, Confucian philosophy, and arts, while Japan also developed unique cultural components.
Step-by-step explanation:
The country that had a profound effect on the culture and literature of early classical Japan was China. During the Tang dynasty, Japan adopted the Chinese writing system and was influenced by Confucian philosophy and Chinese arts. Buddhism was introduced to Japan through Korea as a result of close foreign relations, while Confucianism and elements of the Chinese language came directly from Chinese contact.
However, Japan also developed unique aspects of its culture, such as Shintoism, distinct forms of Buddhism, and historical institutions like the samurai and shogun. At the same time, Japanese aristocracy took to writing poetry in both the imported Classical Chinese and in native scripts: Katakana and Hiragana, which represented a blend of Chinese influence and indigenous development.