Here are five essential facts about one of the world’s oldest and most cloistered royal families.

Share story

Emperor Akihito of Japan indicated in a rare public address Monday that he wants to abdicate the throne, which would make him the first Japanese monarch in 200 years to step down. Here are five essential facts about one of the world’s oldest and most cloistered royal families.

A Lengthy Dynasty

The imperial house of Japan is the oldest continuous monarchy in the world.

Akihito is the 125th emperor in a line that extends back to the country’s founding in 600 B.C. by the Emperor Jimmu, who legend holds was descended from the sun goddess. Although evidence of the first 25 emperors is shrouded in myth, there is ample historical proof of an unbroken hereditary line from A.D. 500 to today.

After modern Japanese emperors die, their names are changed to reflect the era in which they ruled. Akihito will be renamed Heisei (“peace everywhere”) for the name of his era, which began with his coronation in 1989. His father, the wartime emperor Hirohito, is posthumously known as Showa, or “radiant Japan.”

Gods and Men

The emperor is the head of state and the highest authority of the Shinto religion.

Japan is the only modern nation to still refer to the head of its royal family as emperor. In Japanese the emperor is called tenno, or “heavenly sovereign,” a nod to the idea that the imperial family is descended from gods. The monarchy historically maintained a divine right to rule, but it was only in recent centuries that cults around the emperor began to deify rulers as demigods.

Soon after the end of World War II, as part of Japan’s surrender, Hirohito renounced what he called the “the false conception that the emperor is divine.” Under Japan’s 1947 postwar constitution, the emperor became “the symbol of the state and of the unity of the people,” a figurehead with no political authority.

Amateur Scientists

At the beginning of each new year since 1869, just after Emperor Meiji restored the authority of the emperor and set Japan on a course of modernization and industrialization, the emperor has hosted a series of scientific lectures.

Hirohito and his elder son, Akihito, shared an interest in marine biology. Hirohito wrote several scientific papers on hydrozoa, a class of aquatic animals related to jellyfish, and Akihito is considered an expert on goby fish. Akihito has written 38 scientific articles on the fish, and a newly discovered species of the fish was named for him.

Women in Power

Historically, women could ascend to the throne and rule in their own right, but only eight of Japan’s emperors have been women.

Until the 20th century, Japanese emperors usually had a chief wife and several concubines, all of whom were members of noble families. Akihito was the first emperor permitted to marry a commoner, and he did, marrying Michiko Shoda in 1956 after meeting her on a tennis court, launching a tennis boom in Japan.

Akihito’s elder son, Crown Prince Naruhito, also married a commoner, Masako Owada, a former diplomat. Princess Masako was given a diagnosis of a clinical psychiatric condition in 2006, believed to have been triggered by the pressures to deliver a male heir.

Under Japan’s Imperial Household Law, only a male heir can inherit the throne, although a change in the law was briefly considered in 2005 to allow a woman to become emperor. Those plans were dropped after Princess Kiko, the wife of Akihito’s second son, Prince Akishino, gave birth to a son, who can inherit the throne.

The Imperial couple’s third child, Princess Sayako, became Sayako Kuroda when she married a commoner in 2005 and left the Imperial family.

The Chrysanthemum Throne

Akihito and his family live in the Tokyo Imperial Palace, a parklike compound in Japan’s capital that is considered one of the most expensive pieces of real estate in the world.

The palace includes residences for the imperial family, the offices of the Imperial Household Agency and museums. The monarchy is often referred to metaphorically as the Chrysanthemum Throne, but there is an actual chrysanthemum throne, an ornate chair called takamikura on which the emperor sits during his enthronement ceremony.