On the death of his father in 1811, he was adopted by his elder brother, the 4th daimyo of Sakura, Hotta Masachika, to secure the family succession.

Almost immediately, the domain was saddled with the fiscally taxing burden of improving coastal defenses in Edo Bay against incursions of the Black Ships.

However, Masayoshi proved an able administrator, reforming the domain's finances, sponsoring studies of rangaku, especially western military science, and establishing the predecessor of Juntendo University.

Returning to Sakura, Hotta remained one of the leaders of the party supporting ending the sakoku isolation policy and opening the country to foreign trade.

[3] Based on his knowledge of the events of the Arrow War, Hotta believed that a violent response from the United States would arise if the demands of American consul Townsend Harris were refused.