After that, 'A Material for the Boshin War' by Minoru MUSHANOKOJI ("Shigaku zasshi" (Journal of Historical Studies), Vol. 61, No.8, 1953) and 'Regarding so-called Taisei Kaigen (changing era name to Kaigen)' by Eikichi KAMATA ("Shudaishigaku" (in-house magazine of historical study group in Akita University, Akita Prefecture), No. 14, 1967) followed, then detailed study was complied in 'Consideration for establishment of so-called 'Tohoku Chotei (the Tohoku Court) in 1868' by Noriyuki FUJII ('New Study of Modern Japanese History 1') in 1981.
その後、武者小路穣の「戊辰役の一資料」（『史学雑誌』第61編8号、昭和28年）、鎌田永吉の「いわゆる大政改元をめぐって」（『秋大史学』14号、昭和42年）と続き、昭和56年、藤井徳行「明治元年所謂「東北朝廷」成立に関する一考察」（「近代日本史の新研究1」）で詳細な研究がまとめられた。