Japan’s Prince Hisahito is the first male royal to reach adulthood in 40 years. He may be the last

Japan's Prince Hisahito, nephew of Emperor Naruhito, attends his first press conference to commemorate his coming-of-age at the Akasaka Estate residence in Tokyo on March 3, 2025. (Japan Pool/Kyodo News via AP)

TOKYO — Japan’s Prince Hisahito is the first male royal to reach adulthood in 40 years. He could also be the last.

The elaborate palace rituals to formally recognize Hisahito as an adult on Saturday are a reminder of the bleak outlook for the world’s oldest monarchy. Much of this comes down to its male-only succession policy and dwindling numbers.

Hisahito is second in line to the Chrysanthemum Throne and is likely to become emperor one day. After him, however, there is nobody left, leaving the Imperial family with a dilemma over whether they should reverse a 19th century ruling that abolished female succession.

Hisahito is a university freshman who loves bugs

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 fall a year after he turned 18, reaching legal adulthood, because he wanted to concentrate on college entrance exams.

He may be the last emperor

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 the prewar Constitution for the first time in 1889. 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.

A succession debate rages

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.”

Crown, horse-carriage and prayers

Saturday’s ritual for Hisahito was to start at his family residence, with him appearing in a tuxedo to receive a crown to be delivered by a messenger from Naruhito. He then was to put on traditional attire which symbolizes his pre-adulthood status to visit the Imperial Palace to perform a crown-wearing ritual.

After changing into a costume which symbolizes adulthood, he is scheduled to ride in a royal horse carriage to pray at the three shrines within the palace compound.

In the afternoon, Hisahito will put his tuxedo back on to visit the Imperial Palace to greet Naruhito and Empress Masako in the prestigious Matsu-no-Ma, or pine room. In another ritual he is to receive a medal, the Grand Cordon of the Supreme Order of the Chrysanthemum, in a postwar tradition. He will also greet his grandparents, Akihito and his wife, former Empress Michiko, at their palace.

In the evening, Akishino and Kiko will host a private celebration for their son at a Tokyo hotel where their relatives will gather.

The rituals also include his visits early next week to Ise, Japan’s top Shinto shrine, the mausoleum of the mythical first emperor Jinmu in Nara, as well as that of his late great-grandfather, wartime emperor Hirohito, in the Tokyo suburbs. He will also have lunch with Prime Minister Shigeru Ishiba and other dignitaries Wednesday.

Mari Yamaguchi, The Associated Press