The Meiji state, in constructing a nation centered on the emperor, erected several “pillars”: an unbroken imperial line (bansei ikkei), strict male-line succession, sacred regalia from the gods, and rituals said to date from time immemorial. All were presented to the public as ancient, unchanging tradition. But when each pillar is tapped, one by one, it turns out to be either hollow or filled with concrete poured only in the modern era.
This first part examines four pillars belonging to the foundation: bloodline and genealogy.
Pillar 1: The Very Term “Bansei Ikkei”
What Meiji claimed: Article 1 of the Meiji Constitution states that “the Emperor… shall reign over and govern” as part of “a line unbroken for ages eternal.” A bloodline unbroken since the first emperor, Jinmu, is presented as the basis of the Japanese state’s legitimacy.
Historical fact: The term bansei ikkei itself traces back to October 1867, when Iwakura Tomomi used the phrase in his memorandum “On the Restoration of Imperial Rule” (Ōsei Fukko Gi), writing that “the imperial house has issued forth, unbroken across ages, as a single lineage.” In other words, the term was not self-evidently ancient at all — it was coined by Iwakura, in the final months of the Bakumatsu period, specifically to legitimate the restoration of imperial rule. Some 22 years later, in 1889, it was Inoue Kowashi who led the work of incorporating this already-existing term into Article 1 of the Meiji Constitution, fusing nativist (kokugaku) discourse with Prussian constitutional theory (advised by figures such as Stein and Mosse) to turn it into a full theory of rule staging imperial sovereignty as “historical continuity.” Genealogically, the existence of the first nine emperors (the so-called “eight unrecorded reigns”) cannot be verified in any historical source, and mainstream historiography treats them as mythic constructions from the Kojiki and Nihon Shoki.
Seen from a global perspective: Eric Hobsbawm and Terence Ranger’s concept of “invented tradition” originally developed out of analysis of Victorian British royal ritual. As David Cannadine’s research shows, staging “ancient tradition” to achieve national integration was a pattern widely shared across 19th-century European nation-building. Japan’s bansei ikkei discourse can be relativized as one variant of this global current. What is unusual is not that it was constructed, but that it continues to circulate today as though it had never been constructed at all.
Pillar 2: The Absolutism of Male-Line, Male Succession
What Meiji claimed: The imperial throne must be inherited exclusively through the male line by male heirs, and this is “tradition.”
Historical fact: In reality, eight women reigned as tenno across ten reigns — including Suiko, Jitō, Genmei, Genshō, Kōken/Shōtoku, Meishō, and Go-Sakuramachi. Genealogical continuity itself has also been strained at points: Emperor Keitai (traditionally the 26th emperor) was brought to the throne from a branch five generations removed from Emperor Ōjin — a genealogically distant connection even by the standards of the time. Scholars such as Yoshie Akiko have suggested that this “connection” itself may have been a retrospective political legitimation. In short, “one line through the male line” was not a fact carried through history unbroken, but a story flexibly managed at each period and only later reconstructed as a single continuous thread.
Seen from a global perspective: Most surviving monarchies today — the UK, Spain, the Nordic countries — have already shifted to absolute primogeniture regardless of sex. From a comparative standpoint, treating insistence on strict male succession as unquestionable “tradition” is, if anything, the outlier among contemporary monarchies rather than the norm.
Pillar 3: The Legitimacy Dispute Over the Northern and Southern Courts — When the State Rewrote Its Own Genealogy
What Meiji claimed: The imperial line has continued as a single, undisputed line.
Historical fact: From 1336 to 1392, Japan had two rival imperial courts — the Northern Court (Kyoto) and the Southern Court (Yoshino) — each using its own era names. The present imperial family descends genealogically from the Northern Court. Yet in 1911, following a Diet controversy over how to treat this period in textbooks, the Meiji government — with the emperor’s own sanction — ruled the Southern Court legitimate in state textbooks. In other words, in order to assert “the present imperial house is legitimate,” the state formally legitimized a court from which the current family is not descended — an operation in which genealogy and political legitimacy were made to diverge. The story of bansei ikkei already contained an internal contradiction, and there is a documented precedent of the state rewriting it by political decision.
Seen from a global perspective: This closely parallels cases in Europe where rival royal houses contested legitimacy and the eventual victor retroactively tidied up the genealogy — such as Tudor genealogical revisionism after the Wars of the Roses. The myth of “a single bloodline” is, in many cases, a story edited after the fact by the winner.
Pillar 4: The Kan’in-no-miya House — An 18th-Century Insurance Policy
What Meiji claimed: The imperial line has continued naturally, unbroken, as a single bloodline.
Historical fact: The current imperial line (from Emperor Kōkaku onward) is in fact connected through a collateral branch house newly established in the mid-Edo period. On the advice of Confucian scholar Arai Hakuseki, the Kan’in-no-miya house was created in 1710 as a hedge against the risk of succession failure. When the main line did in fact nearly fail, Emperor Kōkaku ascended from this Kan’in-no-miya house, directly connecting to the present imperial family. In other words, bansei ikkei was not the natural continuation of a single bloodline, but the product of institutional design — maintained by an artificially engineered backup system created in the 18th century.
Seen from a global perspective: This resembles the institutional mechanisms European royal houses used to prepare collateral branches against extinction — such as Britain’s Act of Settlement routing succession to the Hanoverian line. It should be compared not as “the natural continuation of a bloodline” but as “continuity by institutional design.”
Summary of Part I
The foundation of bloodline has at least four visible seams: ① the term bansei ikkei itself is a product of modern political theory; ② absolute male-line succession does not match historical fact; ③ there is a precedent of the state itself rewriting genealogical legitimacy by political decision; and ④ continuity itself was an artificially engineered institution designed in the 18th century.
None of this is simply a story of “the Meiji government lying.” Rather, the paradox is that bloodline — which appears to be the most immovable foundation of all — has in fact been the most frequently patched, rewritten, and re-engineered element.
Part II will examine the superstructure built atop this foundation of bloodline: the Kojiki/Nihon Shoki myths, the three sacred regalia, State Shinto and Yasukuni, and the backward-calculated antiquity of the imperial era system.