The area of Nagaokakyō was part of ancient
Yamashiro Province. The legendary
Kofun period Emperor Keitai's Prince Otokuni, constructed a palace in this location in 518 AD. In 784 AD,
Emperor Kammu transferred the
capital of Japan from
Heijō-kyō to the
Nagaoka-kyō Palace; however, the palace was not actually located in modern Nagaokakyō, but in the adjacent city of
Mukō . The villages of Otokuni, Kaiin-ji and Shinkotari in
Otokuni District, Kyoto were established on April 1, 1889, with the creation of the modern municipalities system. These villages merged on April 1, 1949, to form the town of Nagaoka, which was elevated to city status on October 1, 1972, taking the name of Nagaoka-kyō. ==Government==