A freshman at Tsukuba University near Tokyo, Hisahito studies biology and enjoys playing badminton. He is especially devoted to dragonflies and has co-authored an academic paper on a survey of the insects on the grounds of his Akasaka estate in Tokyo.
In his debut news conference in March, the prince said he hopes to focus his studies on dragonflies and other insects, including ways to protect bug populations in urban areas.
Hisahito was born on Sept. 6, 2006, and is the only son of Crown Prince Akishino, the heir to the throne, and his wife, Crown Princess Kiko. He has two older sisters, the popular Princess Kako and former Princess Mako, whose marriage to a nonroyal required her to abandon her royal status.
Hisahito’s coming-of-age rituals fell a year after he turned 18, reaching legal adulthood, because he wanted to concentrate on college entrance exams.
Hisahito is the nephew of Emperor Naruhito, who has one child, a daughter, Princess Aiko. Hisahito's father, Akishino, the Emperor's younger brother, was the last male to reach adulthood in the family, in 1985.
Hisahito is the youngest of the 16-member all-adult Imperial Family. He and his father are the only two male heirs who are younger than Naruhito. Prince Hitachi, former Emperor Akihito's younger brother, is third in line to the throne but is already 89.
The shortage of male successors is a serious concern for the monarchy, which historians say has lasted for 1,500 years. The issue reflects Japan’s rapidly aging and shrinking population.
Japan traditionally had male emperors, but female succession was permitted. There have been eight female emperors, including the most recent Gosakuramachi who ruled from 1762 to 1770. None of them, however, produced an heir during their reign.
Succession was legally limited to males by law for the first time in 1889 under the prewar Constitution. The postwar 1947 Imperial House Law, which largely preserves conservative prewar family values, also only allows male succession.
But experts say the male-only succession system is structurally flawed and only worked previously thanks to the help of concubines who, until about 100 years ago, produced imperial children.
Hugely popular Princess Aiko, the only daughter of Emperor Naruhito and Empress Masako, cannot be her father’s successor, even though she is supported by much of the public as a future monarch.
To address succession concerns, the government compiled a proposal to allow a female emperor in 2005. But Hisahito's birth quickly changed the tide and nationalists turned against the proposal.
A separate, largely conservative panel of experts in January 2022 recommended calling on the government to maintain its male-line succession while allowing female members to keep their royal status after marriage and continue their official duties. The conservatives also proposed adopting male descendants from now-defunct distant royal families to continue the male lineage.
But the debate has stalled over the question of whether to give royal status to nonroyals who marry princesses and their children.
The stalled debate has forced Hisahito to carry the burden of the Imperial Family's fate by himself, former Imperial Household Agency chief Shingo Haketa said in a Yomiuri newspaper article earlier this year. “The fundamental question is not whether to allow male or female succession line but how to save the monarchy.”
The conservative Yomiuri issued its own proposal in May, calling for an urgent revision to the Imperial House Law to give royal status to husbands and children of princesses and allow women to succeed the throne. It called on the parliament to “responsibly reach a conclusion on the crisis surrounding the state and the symbol of the unity of the people.”
