Kōō (Nanboku-chō period)

Kōō (康応^?), also romanized as Kō-ō, was a Japanese era name (年号, nengō, lit. year name) of the Northern Court during the Era of Northern and Southern Courts after Kakei and before Meitoku. This period spanned the years from February 1389 to March 1390. The emperor in Kyoto was Emperor Go-Komatsu (後小松天皇, Go-Komatsu-tennō^?) The Southern Court rival in Yoshino during this time-frame was Emperor Go-Kameyama (後亀山天皇, Go-Kameyama-tennō^?).

During the Meiji period, an Imperial decree dated March 3, 1911 established that the legitimate reigning monarchs of this period were the direct descendants of Emperor Go-Daigo through Emperor Go-Murakami, whose Southern Court (南朝, nanchō^?) had been established in exile in Yoshino, near Nara.

...
Wikipedia