Ōuetsu Reppan Dōmei

Ōuetsu Reppan Dōmei
奥羽越列藩同盟
FormationSpring 1868 (1868)
TypeMilitary and political alliance
HeadquartersShiroishi, Sendai Domain, Japan
Membership31 domains of Northern Japan
Official language
Japanese
Meishu (Alliance Head)
Prince Kitashirakawa Yoshihisa
Sotoku (Governor-General)
Date Yoshikuni, Uesugi Narinori

The Ōuetsu Reppan Dōmei (奥羽越列藩同盟; lit.'Alliance of the domains of Mutsu, Dewa, and Echigo') was a Japanese military-political coalition established and disestablished over the course of several months in early to mid-1868 during the Boshin War. Its flag was either a white interwoven five-pointed star on a black field, or a black interwoven five-pointed star on a white field. It is also known as the Northern Alliance (北部同盟, Hokubu Dōmei).