The Imperial succession came in accordance with the Constitution and a special law allowing 85-year-old Emperor Akihito to abdicate.

Then Crown Prince Naruhito and Crown Princess Masako. (Pool photo)

The new emperor is the first from the post-World War II generation and is the third emperor as the symbol of the state and of the unity of the people as stipulated under the Constitution introduced after the war.

The Imperial era of Heisei, which was ushered in on Jan. 8, 1989, came to an end, making way to the new era of Reiwa.

The Emperor's abdication was the first in 202 years since late Edo-period Emperor Kokaku stepped down and Emperor Ninko succeeded to the throne. Emperor Akihito became Emperor Emeritus and Empress Michiko, 84, became Empress Emeritus.

With Crown Prince Naruhito, 59, assuming the throne, Crown Princess Masako, 55, became the new empress.

New Emperor Naruhito will attend ceremonies related to his enthronement on May 1, which are part of acts in matters of state. From 10:30 a.m., a ceremony called "Kenji-to-Shokei-no-gi" will be held at the "Matsu no Ma" room at the Imperial Palace. During the rite, the new emperor inherits the sacred sword and jewel, which are part of the Imperial Regalia, as well as the State and Privy seals that are used in acts in matters of state.

From 11:10 a.m., a ceremony called "Sokui-go-Choken-no-gi" will be held in the "Matsu no Ma" room, where the new emperor will address the nation, his first on the throne.

According to the Imperial Household Agency, the new emperor became the 126th emperor of Japan. He was called Prince Hiro (Hiro-no-Miya) before he became crown prince. He studied at the Gakushuin schools in Tokyo from kindergarten through graduate school. While in graduate school, he studied at the University of Oxford in the United Kingdom, and is the first emperor to have studied abroad. He married the new Empress in June 1993 and their daughter Princess Aiko, now 17, was born in December 2001.

As the new Imperial Couple does not have a male child, there is no position of "Kotaishi" (crown prince).

With the new emperor acceding to the throne, his younger brother Prince Akishino, 53, becomes "Koshi" (Crown Prince) and the first in line to the throne.

Crown Prince Akishino's son, Prince Hisahito, 12, becomes second in line, followed by Prince Hitachi, 83, the younger brother of Emperor Emeritus Akihito.

On Aug 8, 2016, a video message in which Emperor Akihito indicated his apparent desire to abdicate was released. In the video message, the Emperor stated, "when I consider that my fitness level is gradually declining, I am worried that it may become difficult for me to carry out my duties as the symbol of the State with my whole being as I have done until now."

As the Constitution and the Imperial House Law do not have provisions for an emperor's abdication, the government set up a panel of experts to discuss the issue and began to develop relevant legislation.

On June 9, 2017, a special bill to allow Emperor Akihito to abdicate was passed into law. The one-time law was promulgated on June 16 that year.

In December that year, the date for abdication was decided at a Cabinet meeting, after the matter was discussed at the Imperial House Council including representatives of the Imperial Family and heads of the three branches of the government.

The new Imperial Couple and their daughter will reside at their current residence at the Togu Palace in Tokyo's Minato Ward for the time being. After the Emperor Emeritus and Empress Emeritus move out of the Imperial Residence at the Imperial Palace in the capital's Chiyoda Ward to the Takanawa Imperial Residence, also in Minato Ward, the new emperor's family will move into the Imperial Residence.

After renovations to the Togu Palace are completed, the Emperor Emeritus and Empress Emeritus will move into the palace. The residence will be renamed "Sento Residence," which means the residence of the retired emperor.

VNF/Mainichi