I think the parallels to Japan are interesting. Outo is obviously supposed to be a parallel to Kyoto. The island being split between civilization in the South and hairy barbarians to the North was a real thing in Japanese history. The Japanese - Yamato Japanese, that is - conglomerated in the South of Japan with Kyoto - Heian-Kyo - being relatively far North to the major population centers of the time. In the North, there were the Emishi, a race of notably hairy Asians that even the Chinese were weirded out by (the Japanese sent some Emishi slaves to China as a gift).
Long story short, the Yamato Japanese essentially wiped out the Emishi, unifying Honshu and then spent a millennium working on conquering the Ainu in Hokkaido. The guy who finally conquered the Emishi became the first Shogun of Japan. The title, Sei'i Taishogun would be shortened to Shogun and wielded as a title by Minamoto no Yoritomo who became the real leader of Japan after winning the samurai civil war.