Japan Enacts Male-Only Imperial Succession Law, Raising Concerns Over Monarchy's Future

Japan's parliament on Friday approved a historic revision to the Imperial House Law , reaffirming that only men from the paternal imperial bloodline can inherit the Chrysanthemum Throne. The move has sparked widespread debate, with critics warning that it could deepen the succession crisis facing the country's shrinking and ageing imperial family.

The revised law introduces measures allowing distant male descendants of former imperial branches to be adopted into the royal family to help preserve the male lineage. It also permits female royals to retain their imperial status after marrying commoners , although their spouses and children will not become members of the imperial family.

The legislation effectively keeps Princess Aiko , the popular 24-year-old daughter of Emperor Naruhito , ineligible to become emperor because of her gender. Under the succession order, the throne would pass to the emperor's younger brother, Crown Prince Akishino , followed by his 19-year-old son, Prince Hisahito , who is currently the only young male heir. After him, the next in line is the emperor's 90-year-old uncle, Prince Hitachi .

Supporters of the law, including Prime Minister Sanae Takaichi and conservative lawmakers, argue that maintaining an unbroken paternal bloodline is essential to the emperor's legitimacy and to preserving centuries-old traditions.

However, constitutional experts, historians and women's rights advocates have criticised the reforms as reinforcing a patriarchal system while ignoring growing public support for allowing female monarchs. They argue that the monarchy's long-term stability remains uncertain, given the limited number of male heirs and Japan's declining population.

Japan has had eight female emperors throughout its history, although the current male-only succession rule was first codified in the 1890 Imperial House Law and largely retained after World War II.

The revisions have reignited national debate over whether tradition should outweigh gender equality in determining the future of one of the world's oldest hereditary monarchies.