Line of succession to the Japanese throne
The current line of succession to the Chrysanthemum Throne is based on the Imperial Household Law. At present, only males are allowed to succeed to the throne.
The list below contains all princes currently eligible to succeed to the throne.
The list below contains all princes currently eligible to succeed to the throne and the princesses who would be eligible to succeed if cognatic primogeniture were to be adopted.
The Imperial House Law of 1889 was the first Japanese law to regulate the imperial succession. Until October 1947, when it was abolished and replaced with the Imperial Household Law, it defined the succession to the throne under the principle of agnatic primogeniture.
In all instances, the succession proceeded from the eldest male heir to the youngest (Ch. I: Article 3). In the majority of cases, the legitimate sons and male heirs of an emperor were favoured over those born to concubines. Illegitimate sons would only be eligible to succeed if no other male heirs existed in the direct line; however, the illegitimate sons of an emperor had precedence over any legitimate brothers of the emperor (Ch. I: Article 4). Those in the line of succession suffering from "incurable diseases of mind or body," or when "any other weighty cause exists," could be passed over with the advice of the Imperial Family Council, headed by the emperor, and after consulting the Privy Council (Ch. I: Article 9).
On 11 February 1907, an amendment was made to the Imperial House Law to reduce the numbers of imperial princes in the shinnōke and ōke, the cadet branches of the imperial family, who were fifth– or sixth-generation descendants of an emperor. The amendment provided for princes to leave the imperial family, either by imperial decree or by imperial sanction. They were then granted a family name and assumed the status of nobles with the peerage titles of marquis or count, thereby becoming subjects (Article I). Alternatively, a prince could be formally adopted into a noble family or succeed to the headship of an imperial family line as a noble (Article II). Under the terms of the amendment, those former princes and their descendants who left the imperial family were excluded from the line of succession and made ineligible to return to the imperial family at any future date (Article VI).
As of October 14, 1947, when the Imperial Household Law abolished the shinnoke (Princely Houses of the Blood) and oke (Princely Houses) cadet branches, the immediate line of succession to the Japanese throne was as follows:
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