This was because, after Ansei no Taigoku (a purge by the Shognate in an effort to suppress extremists) carried out by Tairo (chief minister) Naosuke II, Yoshinaga MATSUDAIRA was forced to abdicate the headship of the family and was suspended from the office.
大老井伊直弼による安政の大獄で松平慶永が隠居・謹慎処分となったためである。