Kō

The Kō were a samurai clan of the Ashikaga estate in Shimotsuke, claiming Takashina descent and serving the Ashikaga as hereditary stewards since Kamakura times. Their heyday came under Moronao, Ashikaga Takauji's steward: he sat on the Kenmu board of claims as Takauji's deputy, and under Muromachi he and his brother Moroyasu held highest office, their armies killing Kitabatake Akiie and Kusunoki Masatsura and pressing the Yoshino court to the edge of destruction.

His arrogance pitted him against Takauji's brother Tadayoshi, sparking the Kannō Disturbance of 1350. He briefly ousted Tadayoshi, who then joined the Southern Court and routed him at Uchidehama; after surrendering, the brothers were cut down with most of the clan by Uesugi Yoshinori's men at the Mukō River, and Kanto leader Morofuyu killed himself.

Survivors who sided with Tadayoshi kept the name: Moroari briefly held Kanto Kanrei and Morohide became Constable of Yamashiro and Sado. The Kō later served the Kamakura and Koga Kubō and as shogunal guardsmen, one of them dying beside Ashikaga Yoshiteru in 1565.