On September 20, 1868, the pro-Shōgunate
Ōuetsu Reppan Dōmei was proclaimed at
Morioka, the capital of the
Nanbu clan who ruled
Morioka Domain. The territory of the Nambu extended along the northeastern half of
Mutsu Province, as far north as
Shimokita Peninsula, and the Nambu controlled a subsidiary domain at
Hachinohe. The Nambu clan's hereditary rivals dominated the northwest of Mutsu Province, the
Tsugaru clan of
Hirosaki Domain, with a subsidiary domain at
Kuroishi. The Tsugaru first sided with the pro-imperial forces of
Satchō Alliance, and attacked nearby
Shōnai Domain. However, the Tsugaru soon switched course, and briefly became a member of the Ōuetsu Reppan Dōmei. However, for reasons yet unclear, the Tsugaru backed out of the alliance and re-joined the imperial cause after a few months. The village of
Noheji in what is now part of
Aomori Prefecture was an important port for the Nambu clan on
Mutsu Bay. Noheji was garrisoned by approximately 400 men from Hachinohe Domain after the defection of the Tsugaru back to the imperial side. The port was shelled by
Kubota Domain warship
Shunyo-maru commanded by
Saga Domain's
Nakamuta Kuranosuke on September 10, but with little damage to the village or reported casualties. ==Battle==