Japan’s Imperial Family has survived wars, defeat, occupation, and centuries of political upheaval. But today, the world’s oldest hereditary monarchy faces a threat that may come from its own traditions.

Princess Aiko, Emperor Naruhito’s only child, cannot inherit the Chrysanthemum Throne because she is a woman. Instead, the dynasty’s future rests largely on Prince Hisahito, one of just a handful of remaining male heirs.

As imperial princesses lose their royal status upon marrying commoners and the line of succession continues to shrink, Japan faces a difficult choice between preserving centuries-old traditions and securing the monarchy’s survival.

Can the Chrysanthemum Throne endure without changing the very rules that have defined it for generations?