Imperial Household Law

The Imperial Household Law of 1947 (皇室典範, Kōshitsu Tenpan^?) is a statute in Japanese law that governs the line of imperial succession, the membership of the imperial family, and several other matters pertaining to the administration of the Imperial Household.

It was passed during the Shōwa era on January 16, 1947, by the last session of the Imperial Diet. This law superseded the Imperial Household Law of 1889, which had enjoyed co-equal status with the Constitution of the Empire of Japan and could only be amended by the Emperor. The revised statute is clearly subordinate to the Constitution of Japan, which went into effect on May 3, 1947. It develops Chapter 1: Article 2 of The Constitution of Japan which states: "The Imperial Throne shall be dynastic and succeeded to in accordance with the Imperial House Law passed by the Diet".

Drafted by the government of Shigeru Yoshida, Prime Minister during the American occupation by the Supreme Commander for the Allied Powers, the 1947 statute sought to bring the legislation governing the Imperial Household into compliance with the American-written Constitution.

The law had the effect of dramatically restricting membership in the Imperial Family to the Emperor Hirohito's immediate family, his widowed mother, and the families of his three brothers. It abolished the collateral lines of the Imperial Family, the shinnōke and the ōke, which had traditionally been a pool of potential successors to the throne if the main imperial family failed to produce an heir. The fifty-one members of the eleven cadet branches renounced their Imperial status; and they were formally removed from the Imperial household register and became ordinary citizens on October 14, 1947.

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