Japan's parliament enacted a historic revision to the 19th-century Imperial House Law on Friday, codifying that only males descended from the paternal line can become emperor and adopting measures designed to preserve the male-dominated monarchy.
The revisions include allowing adoption of distant male relatives to father future heirs and permitting princesses to retain their royal status after marrying commoners. The move comes as the imperial family faces a shrinking membership: only five of its 16 adult members are men, and there are no children in the family.
What the Right Is Saying
Prime Minister Takaichi and conservative lawmakers insist male bloodline succession is essential to the monarchy's legitimacy. "I'm deeply moved," Takaichi told reporters after the enactment. She has stated that paternal lineage constitutes "the only source of the emperor's authority and legitimacy."
The paternal-line male succession rule was first established in the 1890 Imperial House Law when Japan promoted patriarchal systems, and it has been retained through subsequent revisions including the current 1947 version. The new measures are intended to solidify this principle by enabling adoption of distant royal male relatives to father future heirs.
Imperial Household Agency chief Buichiro Kuroda said his agency "will do everything it can appropriately to support smooth activity for the Imperial Family members in line with (the revisions), while fully taking into consideration their feelings." Former Imperial Household Agency chief Shingo Haketa told Kyodo News that without these measures, succession after Prince Hisahito would be "extremely unstable."
What the Left Is Saying
Critics of the revision argue it represents an outdated patriarchal system that discriminates against women. Chizuko Ueno, a prominent feminist scholar, called it ironic that Prime Minister Sanae Takaichi, Japan's first female premier, is leading efforts to preserve male-only succession. "The new measures treat male royals as stallions and put female royals under pressure as 'childbearing machines' to produce male offspring," Ueno wrote.
Hideya Kawanishi, an expert on monarchy at Nagoya University, said the revision amounts to a declaration against female monarchs. "They cannot say it's male chauvinism, so they call it tradition," he noted. The changes have sparked protests from Japanese citizens who see them as efforts to eliminate Princess Aiko, Emperor Naruhito's 24-year-old daughter, from the line of succession.
Many ordinary Japanese support allowing Princess Aiko to succeed her father. "The emperor is a symbolic figure, and I don't see why women cannot serve in that role," said Junichiro Tsujimaru, 78, a sushi chain founder. Yoshio Iwase, 78, argued that Aiko, as the emperor's daughter, represents the legitimate successor given that female emperors have ruled Japan before.
What the Numbers Show
The current imperial family has 16 adult members, only five of whom are men. Emperor Naruhito's only heir in his direct line is his 19-year-old nephew Prince Hisahito. The next male in succession is 90-year-old Prince Hitachi, the emperor's uncle. There have been eight female monarchs in Japanese history; the last was Empress Gosakuramachi, who ruled from 1762 to 1770.
In 1947, 51 members from 11 branch families renounced their royal status to ease the postwar financial burden on the monarchy. These individuals are at least 36 generations removed from Emperor Naruhito, having split from a common male-line ancestor approximately 600 years ago. A government proposal in 2005 to allow female monarchs was abandoned after Hisahito's birth in 2006, when he became the first male royal baby born into the family in four decades.
The Bottom Line
The revision represents a significant moment for Japan's 1,400-year-old monarchy as it grapples with demographic decline and shifting social attitudes. While supporters say the measures ensure continuity, critics warn they may accelerate the institution's contraction by alienating a public that increasingly supports gender equality and female succession.
Looking ahead, observers will watch whether any distant male relatives accept adoption into the royal family and how Princess Aiko and other princesses respond to their continued exclusion from the line of succession. The monarchy's future stability depends on whether adopted heirs produce male offspring under what experts describe as intense pressure.