On Msy10, before this incident, Kuniomi attended the Daimyo-gyoretsu (feudal lord's costumed procession) in order to submit a petition to Narihiro KURODA (a lord of Fukuoka Domain who passed by Osaka-jo Castle on the way to his compulsory residence in Edo) complaining about the disturbances and asking for cooperation in raising an army.
国臣はこれより前の4月12日に参勤交代の途上で大坂の近くまで来ていた福岡藩主黒田斉溥へ情勢の不穏と、挙兵への協力を訴える嘆願を提出すべく、大名行列に出頭していた。