On May 6, 1856, he was born in Toranomon, Edo, Musashi Province (present day Minato-ku, Tokyo (Tokyo)), as the fourth son of Hirofusa HATOYAMA, a feudal retainer of Mimasaka-Katsuyama Domain Mimasaka Province (present day Maniwa City, Okayama Prefecture), who was in charge of edo rusuiyaku (a person representing the lord during his absence from Edo).
1856年5月6日、武蔵国江戸虎門（現・東京都港区(東京都)）に美作国美作勝山藩（現・岡山県真庭市）の藩武士鳩山博房（江戸留守居役）の4男として生まれる。