In the ninth century when the private warrior bands (in ancient Japan) became nominal and effectively disappeared, gunji (district officials), the rich and powerful class, and fushu (the indigenous tribes of the north-eastern Japan who became allies of the Imperial Court) were formed as military forces under 'hatsuhei-chokufu' (an imperial order authorizing the mobilization of soldiers).
9世紀に入り、軍団(古代日本)が形骸化し実質的に消滅していくと、郡司・富豪層や俘囚が「発兵勅符」に基づいて軍事力として編成されるようになった。