Because some domains joined the alliance out of sympathy or for opportunity, and others joined it because of pressure from large domains or from coercion by the former Shogunate forces, they were not closely united; accordingly, one domain after another defected from the alliance as the situation worsened.
両藩への同情や日和見的に雰囲気から参加した藩だけでなく、大藩の圧力や旧幕府軍の恫喝を受けて参加した藩もあり、結束が固いとは言い難く、戦況が劣勢になるにつれ次々と同盟から脱落していった。