Kutou (倶東国; Kutou Koku) is one of the four countries in The Universe of the Four Gods. The capital city is Shunrou. A century ago, it was rivaled with Hokkan wanting the land, but later a treaty was signed to resolve the conflict. In the time of Miaka Yūki and Yui Hongo , Kutou's rival is Konan. The Kutou empire respectively lies to the east of Konan.
Watase based Hokkan on Mongolia, Konan on the Song Dynasty of ancient China, and Kutou on Xi'an (one of the Great Ancient Capital's of China). She has stated this in her free talks. Remember that the Book World is only based on ancient China and is not actually China. ~Ran
Like Hokkan, Sairou, and Konan, Kutou is an imperial and hereditary monarchy, having a known emperor. The ruling families and its members have been exposed in scarcity, but the Kutou Emperor is shown in the series and Prince Hakei in the prequel. Under the rule of the Emperor, the Hin Tribe, Nakago's birthplace, was abused and ultimately slaughtered.