Abstract: Due to the characteristics of Japan in the Middle Ages, none of the cloistered rule, the Kuge and the shogunate could act as a government with full function. Therefore, instead of discussing the internal structure of power, it is better to use national activities as a yardstick. When all parties break down barriers and jointly implement policies, medieval Japan could be treated as a nation. To establish the religious order, the Kuge and the shogunate began to adopt a cooperative response method to restrain, appease and even suppress temples and shrines. This kind of activities formed a strong concept of nation. By analyzing the national activities toward the temples and shrines, we can find two periods of upsurge in national activities, which were between the era of Hōgen to Jōkyū(1156—1221)and Kōchō to Kannō(1263—1352). The first period was represented by the new rules that restrained the behaviors of temples and shrines, and the second period was represented by the national prayer activity. During this period, the armed struggle of temples and shrines never ended, and the joint response of the Kuge and shogunate became an important national issue. The formation of Bushi, the litigation system, and the completeness of the official system were all derived from this. During the civil strife, the armed forces of temples and shrines also took the initiative to participate in the struggle for power. In short, the national activities of temples and shrines are an important criterion for examining whether medieval Japan had the concept of a nation. The two upsurge periods of national activities can be regarded as two forms of Japan as a medieval state.

Key words: medieval Japan, national activity, temples and shrines, new public military system