Fourteen domains in Ou held a conference and submitted a petition for the pardon of the Aizu and Shonai Domains to Commander KUJO, but KUJO rejected it; as a result, they modified the plan to petition directly to the Imperial Court and added eleven more domains to sign the Shiraishi pact on May 15.
奥羽14藩は会議を開き、会津藩・庄内藩赦免の嘆願書を九条総督に提出するも却下されたため、朝廷へ直接建白を行う方針に変更し、閏4月23日新たに11藩を加えて白石盟約書が調印。