'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.

Headquartered at Shiroishi Castle, the alliance's nominal head was Prince Kitashirakawa Yoshihisa, the onetime abbot of Kan'eiji Temple in Edo who fled north following the Satsuma–Chōshū takeover of the city, who declared himself "Emperor Tobu" (東武天皇), with Date Yoshikuni of Sendai and Uesugi Narinori of Yonezawa as the head of the Alliance.

Although heteroclite in nature, the Alliance formed of a combination of modern and traditional forces, and mobilized a total of about 50,000 soldiers.

While the alliance was a bold, innovative step that combined the military forces of several dozen domains, it was unable to fully act as a single, cohesive unit, and with the fall of Sendai and Aizu, it effectively collapsed.