The Longest-Reigning Japanese Emperors

When Emperor Akihito abdicates on April 30, he will have reigned for 30 years and 3 months. This is the tenth longest rule of any Japanese emperor to accede to the throne since the Asuka period (593–710). Emperor Shōwa (Hirohito) is the longest-reigning emperor at 62 years, followed by Emperor Meiji at 45 years and 6 months. Historically, however, many emperors ruled for less than 10 years.

Traditional genealogy includes many emperors from before the Asuka period who were said to have ruled for more than 30 years, but there is either insufficient historical evidence for the lengths of their reigns or they are considered purely legendary figures.

Longest Reigning Japanese Emperors Since 593

Blue shading indicates emperors who abdicated. Created by Nippon.com based on materials published by the Imperial Household Agency, the Cabinet Office, and other organizations.

It has been relatively common for emperors to abdicate through Japanese history, and 58 are on record as having done so. Emperor Kōkaku was the most recent, in 1817, however, so it has been more than 200 years since the last time it happened. The current Imperial House Law, introduced after World War II, and its predecessor, enacted during the Meiji era (1868–1912), allowed no provision for emperors to step down during their lifetimes. This meant that special legislation was required to allow Emperor Akihito to abdicate.

(Translated from Japanese. Banner photo: Emperor Shōwa and Emperor Meiji. © Jiji.)