薩長同盟
During the Boshin War of the Meiji Restoration, he permitted the pro-Imperial forces of the Satchō Alliance to cross Hakone Pass without opposition. However, in May 1868 he met with Hayashi Tadataka and other members of the pro-Tokugawa resistance and indicated his willingness to support their cause. With the fall of Edo to the Satchō Alliance, he changed sides again, and met with the leaders of the Satchō Alliance in Edo to plead his case. Considered a traitor to the imperial cause, he was ordered to retire from public life, and his titles were transferred to Ōkubo Tadayoshi, daimyō of Ogino-Yamanaka Domain, a cadet house of the Odawara Domain.