Final answer:
The Chinese were the foreign people who most influenced the Japanese in the 400s by bringing cultural, political, and religious influence.
Step-by-step explanation:
The foreign people who most influenced the Japanese in the 400s were the Chinese. During this period, known as the Asuka period, Japan experienced significant cultural, political, and religious influence from China. The Japanese adopted aspects of Chinese language, writing system, governance, Buddhism, and architecture, among other things. This period marked a transformative phase in Japanese history, thanks to the influence of the Chinese.
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