Introduction: Starting from Japan’s Half-Hearted Adoption of Confucianism
The two earlier essays, “The Male-Line Succession Myth” and “Equal Opportunity Exists, So Why Can’t Women Rise?”, found that in both family succession and contemporary corporate society, sex is the one constant that never moves, while bloodline, ability, and aptitude are all variables supplied after the fact. This essay returns to the origin itself: where did this consistent structure actually come from?
Japan’s adoption of Confucianism was, compared with China or Korea, clearly partial. Neither the clan-lineage (zongzu) system nor the imperial examination system took root; Confucianism functioned mainly as an educational and governing ethic for the samurai class, selectively adopted by the shogunate. And yet Japanese society retains, to this day, a remarkably rigid norm of male-line supremacy in family life.
The explanation usually offered for this gap is that “the samurai’s traditional patriarchy was generalized into a national norm from the Meiji era onward.” But this explanation itself demands scrutiny. The very category of “samurai patriarchy” is likely a retrospective narrative — one that takes a specific, short-lived period of practice, in which ideal and reality never fully aligned, and tells it as though it were a single, consistent tradition running through samurai society as a whole. This essay traces the inheritance customs of samurai households era by era, from the medieval period through the Meiji era, and carefully reconstructs the outline of this “invented tradition.”
I. The Medieval Period (Kamakura and Muromachi Eras) — When Women Were “Gokenin”
Women were never marginal figures within the Kamakura shogunate’s gokenin (vassal) system. “Female gokenin” — women who inherited fiefs in their own right and bore military and service obligations to the shogunate — were not limited to towering exceptions like Hōjō Masako; they were unremarkable among ordinary samurai households.
- Inheritance in the Kamakura period was fundamentally partible: fiefs were divided among children regardless of sex, as the standard practice.
- The Goseibai Shikimoku legal code (1232) explicitly permitted a woman to adopt an heir to inherit her fief — clear legal recognition of women as agents of family continuity.
- The Muromachi era saw a gradual shift toward single-heir succession (the sōryō system) to prevent the fragmentation of fiefs, but even at this stage, the norm that the heir must be male was not absolute.
In short, the samurai class in its early form was bilateral and relatively flexible, with women fully capable of holding property and inheritance rights. The premise that “samurai originally valued the male line” simply does not hold for this era.
II. The Warring States Period — A Pragmatism That Would Use Any Means to Preserve the House
Looking at succession in the great warlord houses of the Sengoku period, what governed was not a principle of bloodline but a flexible pragmatism that would use any available means for the sake of the house’s survival.
- The existence of female castle lords (Ii Naotora being the best-known example, among several recorded cases) shows women governing as head of a house in the absence of a male heir.
- What mattered most in choosing a warlord’s successor was not whether the heir was biological or adopted, eldest or second son, but sheer capacity to keep the house alive under the selective pressure of civil war. Women were married into other houses to cement alliances, valued as diplomatic linchpins, while men with no blood tie were routinely adopted as sons-in-law and given the headship. Examples abound.
- In other words, for the samurai houses of the Sengoku period, “male-line blood” — much like in the merchant houses of the later Edo period — was a variable readily sacrificed in the face of the practical necessity of survival. Governing ability, military strength, and the maintenance of alliances took priority over any attachment to bloodline.
III. The Edo Period — A Gap Between the Ideal of Male-Line Succession and the Reality of Dependence on Adoption
It was actually in the Edo period — once the wars had ended and the samurai had become bureaucrats — that “samurai patriarchy” began to harden into something institutional. And even then, what became established was not a thoroughly enforced practice but an ideal that continued to be voiced without ever being matched by reality.
- The shogunate initially enforced strict rules against “deathbed adoption” (banning, in principle, a last-minute adoption when a lord died suddenly without an heir). This produced a wave of house extinctions (kaieki) for lack of an heir, generating a large population of masterless samurai (rōnin) and social unrest (cited as one cause of the Keian Uprising led by Yui Shōsetsu). The shogunate later relaxed this ban — which, read the other way, is evidence of just how unstable samurai succession actually was, and how routinely it depended on adoption.
- As the sankin-kōtai system and fixed status hierarchies took hold, and as Neo-Confucianism (shushigaku) was adopted as official state learning, stably passing on family rank, headship, and name became a matter of survival for the samurai bureaucratic class as a whole. It was only at this point that the Neo-Confucian ideal of patrilineal succession began to be seriously articulated, tied to this governance necessity.
- In practice, however, adoption — including of people with no blood relation at all — remained extremely common across daimyo and hatamoto houses. While “single-heir succession by a biological, male-line son” was voiced as the ideal, actual practice continued to rely on flexible adoption, and the gap between ideal and reality was never closed throughout the entire Edo period.
In other words, “samurai patriarchy” in the Edo period should be understood not as a norm actually enforced in practice, but as an ideal that was constantly spoken of while being just as constantly circumvented in practice.
IV. Merchant Houses and Farming Families — Two Classes Even Less Attached to Bloodline Than the Samurai
If the reality of “samurai patriarchy” was this unstable, an obvious question follows: what about merchant houses and farming families, which together made up the majority of society? The short answer is that both classes were even less attached to bloodline principle than the samurai, with the practical survival of the business or the household consistently overriding it.
Merchant Houses: Managerial Competence, Not Bloodline, Was the First Principle
In the great merchant houses of the Edo period — the Mitsui, Kōnoike, Sumitomo families and others — it was standard, not exceptional, to rigorously assess a biological son’s competence and character and disinherit him outright if he was judged unfit. The widely shared Ōmi merchant proverb that “the third generation ruins the fortune” shows that automatic succession by bloodline was actively regarded as a risk to the survival of the business. There is no shortage of examples of a capable head clerk (bantō) being brought in as an adopted son-in-law and given the headship over a biological son, and some great houses — such as the Mitsui family’s “Ōmotokata” system — had genuinely meritocratic governance structures, in which the family as a whole would deliberate collectively to place the most capable person in charge of each branch store.
Even more telling was the practice of noren-wake — setting up a capable head clerk in an independent branch business, extending the house’s brand and reputation without any blood relation at all. Here, blood was scarcely even a consideration; what was being handed down was the shop name, the trademark, and operational know-how — purely economic assets. Women’s roles here differed markedly from the samurai household’s inner quarters: in Osaka merchant houses in particular, it was commonly recorded that the okami (proprietress) held substantial managerial authority — bookkeeping, supervising employees — and it was not unusual for a widow to hold real power as guardian-manager after her husband’s death. In short, the merchant “house” functioned less like a kinship group and more like a corporation, one that was constantly exposed to selective pressure from the market.
Farming Families: Partible Inheritance and Regional Variation in the Sense of “Household”
Among farming families, regional and period variation was in fact substantial, and no single “patrilineal patriarchy” can describe the whole. From the medieval period into the early modern era, partible inheritance was widely practiced in many regions; but from the mid-early-modern period onward, as opportunities for new land reclamation shrank, more regions shifted toward single-heir succession (usually the eldest son) to avoid fragmentation.
What is striking is that the object of single-heir succession was, in many regions, not necessarily fixed as “the eldest son.” Ultimogeniture (inheritance by the youngest child, sometimes regardless of sex) was practiced in parts of the Tōhoku and Hokuriku regions, and succession through an adopted son-in-law (muko-yōshi, or irimuko) was, as in merchant houses, widely practiced among farming families as well. The custom of taking in a son-in-law to have an “heiress” continue the household was a thoroughly ordinary inheritance pattern across Japanese rural society generally. From the standpoint of labor value too, women’s agricultural labor — rice planting, weaving, sericulture — was indispensable to a household’s economy; few farming families could afford to devalue an heiress. Where a son existed but was sickly or uncooperative, it was not unusual for a daughter and her husband to be treated as the household’s real bearers. That said, the legal “principle” governing household headship and inheritance — the norm that headship should, in principle, pass to the eldest son — did persist as the nominal order of village society. Here too we find the same pattern seen in medieval samurai society: a nominal patrilineal norm coexisting, continuously, with flexible practice on the ground.
Putting the Whole Picture Together
Summarizing the findings so far in a table:
| Class | Attitude toward bloodline | What was prioritized |
|---|---|---|
| Medieval samurai | Bilateral, flexible | Preservation of fiefs |
| Sengoku-era samurai | Pragmatic, blood as variable | Survival of the house / governing ability |
| Edo-era samurai | Ideal: male-line succession; practice: reliance on adoption | Maintaining family rank (ideal) / governing ability (practice) |
| Merchant houses | Nearly indifferent to bloodline | Managerial competence / business survival |
| Farming families | Wide regional variation; adopted sons-in-law and ultimogeniture common | Securing labor / preserving household property |
No class, examined this way, unconditionally treated “continuity of bloodline through the male line” as absolute. Even the samurai — the class ostensibly most rigorous about bloodline — only began to articulate this as an ideal in the Edo period, and even then relied on flexible adoption in practice right up to the end. Merchant houses, if anything, placed bloodline almost entirely outside the scope of managerial judgment. Farming families routinely let practical necessity (securing labor) override the nominal patrilineal norm.
V. Why Was the Samurai Ideal, of All Things, Chosen as “Japanese Tradition”?
This leaves one question unanswered. If the samurai ideal of male-line succession was never even fully realized in practice, and merchant houses and farming families had far more flexible practical customs, why did Meiji lawmakers deliberately choose the least-realized samurai ideal as “Japanese tradition,” while discarding the more flexible customs of the merchants and farmers?
At least three overlapping reasons appear to explain this choice.
First, the skewed background of the lawmakers themselves. Most of the bureaucrats and legal scholars of the Meiji government came from the former samurai class, and for them, the model of “what a family should be” could hardly have been anything other than the ideal of the class to which they themselves belonged — even if that ideal had never been fully realized in practice. The practical customs of merchant houses and farming families, as the customs of a different social group outside their own lived experience, most likely never even entered the pool of norms considered as candidates.
Second, ease of use as a technique of governance. The merchant houses’ “competence-first” logic and the farming villages’ “flexible, region-by-region inheritance” were, by their very diversity and particularity, difficult to encode into a single uniform national law. The samurai ideal type — single-heir, male-line succession — by contrast, was a simple, uniform model, convenient for codification and systematization, even though it had never matched reality. For a modernizing state project trying to manage the entire population uniformly through a household registry, it was administratively far more efficient to impose a simple ideal nationwide than to try to reflect a complicated reality in law.
Third, the value of “the samurai” as a source of authority. The Meiji state elevated the culture and ethics of the samurai — the ruling class through the end of the Edo period — into a “Japanese virtue” that the entire nation should emulate, redefining it under the nominal banner of equality among the “four classes.” The pragmatism of the merchants and the practical wisdom of the farmers were most likely judged, by comparison, as too “vulgar” to serve as the ideal image the state wished to present to its people. Extending the samurai’s (practically unrealized) noble ideal to the entire nation was seen as carrying far greater value as an instrument of national moral education and integration.
In short, this choice was not the outcome of an empirical assessment of which practice actually worked. It was an extremely arbitrary selection, determined by three forces entirely unrelated to substantive merit: the lawmakers’ own class background, the administrative convenience of governance, and the need for a source of authority. The fact that the more flexible, more effective, and far more widely lived-in customs of merchants and farmers were set aside, while the least-realized ideal of the samurai alone was chosen to represent “Japanese tradition,” speaks eloquently to the fact that this norm is not an empirically valid inheritance, but a construct selected for the convenience of those who held power.
VI. Meiji — Extracting Only the Ideal, and Legislating Away the Flexibility of Practice
The “ie (household) system” created by the Meiji Civil Code (effective 1898) is often described as “the codification of Japan’s traditional family values.” But given the history traced above, this description turns out to describe a very different operation.
What Meiji lawmakers referenced as “Japanese tradition” was not the whole history of samurai society. It was an operation that discarded entirely the flexible bilaterality and pragmatism of the medieval and Sengoku periods, extracted only the ideal that had only begun to be articulated in the Edo period — an ideal never fully realized even in practice — and fixed it into national law with the force of the state. The medieval female gokenin, the Sengoku female castle lords, and the routine practice of blood-unrelated adoption throughout the Edo period were all consigned, in this process, to convenient oblivion as inconvenient facts.
This operation was, moreover, grafted onto imported Western — specifically German/Prussian — family law provisions on patriarchal authority. In the drafting of the Meiji Civil Code, an initial draft based on French law, prepared by Gustave Boissonade, was revised — following the “Civil Code Controversy” (in which critics such as Hozumi Yatsuka argued that “with the Civil Code, loyalty and filial piety perish”) — into a German Pandectist model of family law that granted the household head strong legal powers: consent to marriage, the right to designate residence, control over family property. The very framing of the controversy — “protecting Japanese tradition from an individualist Western civil code” — in fact produced the opposite result: importing a different Western legal system (German law) that actually strengthened patriarchal authority. This imported legal doctrine was further legitimized through the state-integrating ideology of the Imperial Rescript on Education (1890) — the fiction of the nation as a family headed by the Emperor, which recast the authority of a household head within each individual “ie” as a microcosm of the state’s own sovereign power. In other words, the Meiji ie system was:
- An arbitrary extraction of only the most bloodline-rigorous ideal type from samurai history — one that had, in practice, never been fully realized;
- Legally reinforced with imported Western patriarchal legal doctrine; and
- Legitimized with Confucian rhetoric and state ideology, and imposed on the entire nation —
a modern creation assembled from multiple acts of selection and synthesis.
VII. A Design That Survived the Postwar Era — Connections to Today’s Corporate Society and Politics
The Meiji ie system was legally abolished by the 1947 Civil Code reform. Household-head authority and headship inheritance both vanished from the statute books. But this design did not disappear with its abolition — it survived by transforming into a different set of postwar institutions. Two pathways can be traced.
The political pathway: Women’s suffrage was granted in December 1945 (first exercised in the April 1946 general election); under the Meiji constitutional order, women had held neither the right to vote nor the right to stand for election. Japan was not, however, uniquely backward in this respect. Meiji Japan’s restriction of suffrage to men was, if anything, a choice that placed it in step with — or in imitation of — the standards of Western societies at the time. France did not grant women’s suffrage until 1944, Italy not until 1945, and Switzerland had no federal-level women’s suffrage until 1971. The modern nation-state model itself, in its formative period, was designed to effectively restrict “the nation” to men (often propertied men); Japan’s Meiji lawmakers, in building their state on the model of the modern Western nation, imported not only the ideal of patrilineal patriarchy but also this very premise — that suffrage belonged to men — more or less wholesale. Japan’s exclusion of women should therefore be understood not as a product unique to Confucian tradition or samurai ideals, but as the result of a double reinforcement between the design logic of the modern nation-state, then a global standard, and Japan’s own domestic patriarchal ideal. Political capital — party organizations, electoral strongholds, support-group networks, channels for political fundraising — accumulated exclusively in male hands (largely the lineages of those who had inherited household headship) throughout this period. The gap in starting position, already decisive by the time suffrage was granted, has been carried forward for eighty years since as a hereditary structure of candidate selection built on “the three bans” — jiban, kanban, kaban. The striking underrepresentation of women in today’s Diet must be understood not merely as a lag in voter awareness, but as the result of a capital imbalance produced by the Meiji-era institutional design that excluded women from political participation itself — an imbalance that has never been corrected even after suffrage was granted.
The corporate and household pathway: The seniority-based, lifetime-employment model of Japanese employment established during the high-growth era, and the tax and social security systems that supported it — the spousal deduction (the “¥1.03 million wall”) and the Category 3 insured-person system introduced in the 1985 pension reform — were all designed around a single unit: one male breadwinner supporting the household, with a woman remaining at home as an unpaid laborer responsible for housework and childcare. This is a direct inheritance of the logic of the Meiji ie system, which concentrated the household’s representative authority and economic responsibility in a male household head; even after the legal framework of the “ie” was removed, that same logic was carried forward intact through a different institutional apparatus: tax and social security policy. The implicit assumption, in the promotion track to management, that one must be “infinitely available for long working hours,” rests on this same institutionalized division of labor — men devoted to work, women bearing the burden at home.
In other words, the low share of women in management, politics, and business leadership in contemporary Japan — examined at length in the companion essay, “Equal Opportunity Exists, So Why Can’t Women Rise?” — is not the product of an independently arising, purely modern prejudice. It is the result of the Meiji ie system examined in this essay — that construct which selected only the unrealized ideal of the samurai, reinforced it with Western legal doctrine and state ideology, and imposed it on the entire nation — shedding the outer shell of the legal “ie” while transplanting its underlying logic, intact, into the structure of political-capital accumulation and into the institutional design of employment, taxation, and social security. A rigid attachment to a samurai ideal that was never even matched by reality has become, through this long detour, one of the historical starting points for today’s stark gender imbalance in management and politics alike.
Conclusion: The Double Structure of an “Invented Tradition”
What this investigation reveals is that the imperial theory of male-line succession and the patriarchal norms of ordinary society are, in fact, twin stories produced by exactly the same operation. The story of an “unbroken male line since time immemorial” in the imperial house, and the story of “patrilineal patriarchy since the age of the samurai” in ordinary society, are both narratives that arbitrarily extract a specific slice of history — one in which ideal never fully governed reality, even at the time — and retell it as though it had been a consistent tradition since the beginning.
Nor was this operation confined to a selective cut within samurai society alone. Laying the three major classes of Japanese society — samurai, merchants, and farmers — side by side, we find that even the samurai class, ostensibly the most rigorous about bloodline principle, only began to articulate that ideal in the Edo period and continued to rely on adoption in practice right to the end, while merchants prioritized managerial competence and farmers prioritized securing labor, each with far more flexible practices than the samurai. Despite the fact that samurai were a minority of the population — the majority being merchants and farmers — what the Meiji state chose as “Japanese tradition” was the samurai ideal, the one least matched by reality. This choice was made without any regard to which custom was empirically dominant or which had actually functioned — it was decided by forces entirely separate from substance: the lawmakers’ own background (the former samurai class), the administrative convenience of a uniform legal code, and the need for legitimizing authority as state ideology.
The fact that Japan’s adoption of Confucianism was half-hearted actually throws this operation into sharper relief. If Confucian lineage ideals had truly taken deep root in Japanese society, samurai society would have been rigorously patrilineal from the medieval period onward, and that norm would have permeated merchant and farming society as well. In reality, however, women continued for a long time to serve as both heads of household and heirs, even within the samurai class; and even in the Edo period, once Confucian ideals began to be voiced, samurai practice continued to rely on the flexible mechanism of adoption, while merchants and farmers remained, throughout, largely indifferent to bloodline principle as such. Precisely because the adoption was “half-hearted,” the gap between ideal and practice was never closed in any class by the end of the Edo period — and it was exactly that unclosed, most fragile fragment of ideal, belonging to the samurai alone, that the Meiji state selected for its own convenience, pushing aside the far more flexible practical customs of the other classes, and codified into law for the entire nation. If Japan’s male-line supremacy remains, to this day, more legally rigid than that of Confucian states like China or Korea, this is not because Confucianism took deep root here — it is because the modern state, after the fact, completed and imposed on the whole of society the most fragile fragment of an ideal that had never fully taken root in any class to begin with.