After much deliberation, the choice for the Shugoshoku post came down to two domains: Echizen and Aizu. Of the two, Echizen's Matsudaira Yoshinaga already held high Shogunal office as President of Political Affairs (; "seiji sōsai-shoku"), so all attention was then turned to Matsudaira Katamori. As Katamori was ill, Aizu's senior Edo-based councilor Yokoyama Tsunenori was summoned to Edo Castle instead, and given word of the assignment. Katamori sent a retainer back with a request for being excused: "As this is a shogunal order, we not only have no choice but to accept. Furthermore, our domain's founder Lord [Hoshina] Masayuki laid down a direct command to do so in our house code. However, our lord Katamori is still young, and our men are in the north and unfamiliar with conditions in the Capital. If we were to accept this assignment without question, and a one in ten thousand chance of disaster were to strike, we of the Aizu domain could not possibly do it all alone; the Shōgun would have to get involved, as would all of Japan. We would like to consider this carefully." However, the Bakufu would not listen to this refusal. Matsudaira Yoshinaga traveled personally to the Aizu residence, and confronted Katamori with harsh words invoking Aizu's distinguished past as Shogunate functionaries: "If [your founder] Lord Masayuki were still alive, he would accept without a second thought!" Rumors began to circulate that Katamori refused the assignment out of a desire for self-preservation, to which Katamori is said to have responded, "If people start talking like this, it will shame our domain. There is no way I could explain this to the generations of Aizu lords who have gone before me. I have no choice but to accept." News of Katamori's acceptance of the assignment quickly reached Aizu. Two of the domain-based councilors, Saigō Tanomo and Tanaka Tosa, were particularly opposed to the position, not only for the reasons that Katamori initially had opposed it, but also from a financial stance: Aizu, having been recently charged with both coastal defense at Edo Bay and supervision in eastern Ezo (Hokkaidō), was heavily burdened by expense, and could not afford to do any more without risking total financial ruin.