The area of present-day Shiwa was part of ancient
Mutsu Province, and has been settled since at least the
Jōmon period. The area was inhabited by the
Emishi people, and came under the control of the
imperial dynasty during the early
Heian period. During the
Kamakura period, the area was ruled by a branch of the
Northern Fujiwara, followed by the Shiba clan during the
Muromachi period. During the
Sengoku period, the area was conquered by the
Nambu clan in 1588. During the
Edo period, Shiwa prospered as a
post station on the
Ōshū Kaidō highway connecting
Edo with the northern provinces, as well as from its location on the
Kitakami River. Initially part of
Morioka Domain under the
Tokugawa shogunate, from 1684, four villages (Tsuchidate, Katayose, Inato and Kamihirazawa) formed an
exclave of
Hachinohe Domain. During the
Meiji period, this exclave became the village of Shiwa, and the town of Hizume and the villages of Furudate, Mizuwake, Akaishi, Hikobe, Sahinai, Akasawa, ane Nagaoka were established within
Shiwa District on April 1, 1889 with the establishment of the modern municipalities system. These municipalities were merged on April 1, 1955 to form the new town of Shiwa. ==Government==