A prince from each of the Four Imperial Houses of Princes (also called Miyake) comprised of Fushimi no Miya, Arisugawa no Miya, Katsura no Miya (no relation to the current Katsura no Miya) and Kanin no Miya was adopted by the emperor and conferred the title of imperial prince in order to inherit the throne.
伏見宮、有栖川宮、桂宮（現在の桂宮家とは無関係）、閑院宮の四宮家は世襲親王家として代々各宮家の王(皇族)が天皇の猶子（養子の一種）となり、親王宣下を受け世襲した。