Toyonobu was sent into early retirement as punishment during Naosuke II's Ansei no Taigoku (suppression of extremists by the Shogunate) on February 26, 1859 and Toyonori succeeded as family head and became the lord of domain.
安政6年（1859年）2月26日、豊信が井伊直弼の安政の大獄で隠居処分となったため、家督を継承し藩主となった。