Dec. 23 (UPI) — Japanese Emperor Emeritus Akihito turned 88 years old on Thursday and became the oldest living emperor in Japan’s history — even besting his father by a year.

Akihito served as Japan’s emperor between 1989 and 2019. He ascended to the throne upon the death of his father, Emperor Hirohito, when he died at the age of 87. Posthumously, Hirohito is known as Emperor Showa.

The Imperial Household Agency said Akihito is in good health and is living happily in retirement.

Then-Japanese Crown Prince Akihito celebrates his 41st birthday with his wife, Crown Princess Michiko, at Togu Palace in Tokyo, Japan, on December 23, 1974. File Photo by Japanese Imperial Household Agency/UPI

Akihito is the first emperor to celebrate “beiju,” the Japanese term for one’s 88th birthday.

The former emperor stepped down from the Chrysanthemum Throne in April 2019 and was the first Japanese monarch to abdicate in 200 years. He was succeeded by Emperor Naruhito.

Akihito is known for performing scientific research on goby fish between 1963 and 2021 and publishing three dozen papers on the topic.

Akihito is one of just four emperors to assume the royal throne in Japan in the past 100 years.

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