Japan's Prince Hisahito, 2nd in line to throne, reaches adulthood

Prince Hisahito, the nephew of Emperor Naruhito who is second-in-line to the Chrysanthemum Throne, turned 18 on Friday, becoming the first male member of Japan's imperial family to reach adulthood in around 39 years following his father.

The only son of Crown Prince Fumihito, 58, and Crown Princess Kiko, 57, Prince Hisahito joins a dwindling number of adult members of the imperial family, with the 1947 Imperial House Law limiting imperial heirs to males who have an emperor on their father's side and requiring female members to leave upon marriage to a commoner.

"I hope to learn more through each and every experience, absorbing various aspects and growing through them," the prince said through the Imperial Household Agency on the occasion.

In the statement dated Wednesday, he thanked the many people who have supported him over the years, his parents and his elder sisters, adding, "I want to cherish my remaining time at high school."

While it is customary to hold a Coming-of-Age Ceremony and a press conference to mark the occasion, Prince Hisahito's ceremony will be held in the spring of 2025 or later after he graduates high school so as not to affect his studies, according to the agency.

The prince is also the first imperial family member to reach adulthood under Japan's revised Civil Code that lowered the age of adulthood to 18 from 20 in April 2022. Princess Aiko, 22, the only child of Emperor Naruhito, 64, and Empress Masako, 60, celebrated her coming of age after turning 20 in 2021.

Aside from the prince and the crown prince, the only other heir to the Chrysanthemum Throne is the emperor's childless uncle Prince Hitachi, 88.

According to the agency, Prince Hisahito, a third-year student at a high school in Tokyo attached to the University of Tsukuba, is "extremely interested" in natural history, including the habitats of insects, and has been engaged in fieldwork, attending lectures by experts and reading related materials.

File photo shows Prince Hisahito (C), wearing traditional ceremonial attire, accompanied by his parents Prince Fumihito and Princess Kiko, and elder sisters Princess Mako (L) and Princess Kako (R), after attending ceremonies at the Akasaka imperial estate in Tokyo in November 2011. (Kyodo)

Pursuing his longstanding interest in dragonflies that developed during his years at elementary school, he coauthored an academic paper last year on a survey of dragonflies on the grounds of his family's Akasaka Estate residence, which was published in the Bulletin of the National Museum of Nature and Science.

The agency said the prince is "studying hard" to enter a university that would allow him to explore his field of interest further.

The prince has also slowly begun to be involved in royal duties while attending school, including accompanying his father to the national culture festival for high schools in Gifu Prefecture, central Japan, for two days from July 31.

File photo taken in December 2013 shows Prince Fumihito, his wife Princess Kiko and their son Prince Hisahito during their visit to the Cornerstone of Peace monument at the Peace Memorial Park in Itoman, Okinawa Prefecture. (Kyodo)

The number of royal members carrying out such duties has been shrinking, with females marrying out of the family, including the prince's eldest sister, former Princess Mako, 32, who married her university sweetheart in 2021.

The current total stands at 17, with 12 being women, including Princess Aiko and Princess Kako, the prince's 29-year-old sister.

Amid concerns over stable continuation of the imperial family, the male succession rules have been questioned on a number of occasions, most notably under the government of Prime Minister Junichiro Koizumi in 2005 when an expert panel called for allowing women to succeed to the throne as well as scrapping the rule allowing descent only through the male line.

File photo shows Prince Hisahito (C) and his father Crown Prince Fumihito (R) during their visit to an insect research facility at Tamagawa University's College of Agriculture in Machida, western Tokyo, in April 2024. (Kyodo)

But the debate quickly lost steam when Prince Hisahito was born in September 2006 as the first new male member of the imperial family in nearly 41 years.

The government of Prime Minister Yoshihiko Noda led by the now-defunct Democratic Party of Japan proposed in October 2012 enabling female members of the imperial family to establish their own imperial branches even after marriage to commoners.

However, those discussions also lost momentum after Noda was replaced by Prime Minister Shinzo Abe of the Liberal Democratic Party about two months later.

In December 2021, a government panel tasked with studying ways to ensure a stable imperial succession said the issue "should be judged in the future," despite parliament calling on the government to promptly hold discussions on how to achieve stable imperial succession in a 2017 nonbinding resolution.

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