Although Kammu had abandoned universal conscription in 792, he still waged major military offensives to subjugate the Emishi, possible descendants of the displaced Jōmon, living in northern and eastern Japan. After making temporary gains in 794, in 797 Kammu appointed a new commander, Sakanoue no Tamuramaro, under the title Sei-i Taishōgun (Barbarian-subduing generalissimo). By 801 the shogun had defeated the Emishi and had extended the imperial domains to the eastern end of Honshū. Imperial control over the provinces was tenuous at best, however. In the ninth and tenth centuries, much authority was lost to the great families, who disregarded the Chinese-style land and tax systems imposed by the government in Kyoto. Stability came to Japan, but, even though succession was ensured for the imperial family through heredity, power again concentrated in the hands of one noble family, the Fujiwara which also helped Japan develop more.

What was the name of the possible descendants of Jōmon?