In 2015, Takahito Tsutsumitani was tasked with writing a review for a literary magazine on a book titled, “Jibun de Tsukureru 200-nen Kakeizu.” It was a how-to book on creating your own family tree, a pursuit that had become a bit of a fad thanks to the popularity of the NHK documentary series, “Family History,” which explored the ancestral roots of various celebrities — similar to the PBS series “Finding Your Roots” in the United States.
As a writer, Tsutsumitani specializes in topics relating to childhood education. He reviewed the book with the intention of using its suggested guidelines to trace his own lineage along with his 8-year-old son, a journey back in time that he hoped would become a memorable experience for both of them.
“At that point, I was only aware of where my father came from — Kyoto,” says Tsutsumitani, now 46. “But as I began gathering koseki, a whole new, unknown world opened up before us.”
When it comes to family records in Japan, the koseki is paramount. It’s an official family register that documents and certifies the identity of Japanese citizens and their familial relationships — births, adoptions, marriages, deaths, divorce. It’s a system quite unlike anything outside of East Asia.
While creating family trees is a popular pastime that transcends borders, overseas the process tends to center on the individual doing the research, typically starting with collecting a birth certificate and other documents before working back toward parents and grandparents, linking generations one by one on the way. The koseki, on the other hand, is based on the family unit — a husband, wife and their unmarried children — and a new one is created whenever a marriage takes place and a new family is born.
It’s also not without controversy. Critics say the system is outdated and a potential source of societal and legal discrimination, specifically problematic with regard to gender equality, as couples cannot register a marriage without one legally assuming the other’s surname — almost always the husband’s.
Additionally, the koseki helps deal with inheritance matters in a graying society where deaths now far outpace births — 1,590,503 to 758,631 in 2023.
So when Tsutsumitani, a resident of Osaka, began tracing his family roots, he knew where to start. He began by requesting a copy of his koseki tohon, a record of all his family members, from his registered domicile’s ward office. This is opposed to a koseki shohon, which is an abbreviated version of the former that focuses on one specific person.
He received his koseki in two forms: a newer, electronically formatted and horizontally type-written one based on a style introduced in 1994, as well a certified copy of an invalidated family register, an older, vertically hand-written koseki containing the names of his parents, Tsutsumitani’s date of birth, where he was born and from which family register this particular koseki was created from.
He also obtained the joseki, a register of the names of those who have left the family through marriage or death. This was to collect as much information as possible since a person who died or was transferred in a previous family register will not be listed in the new family register, and changes in family structure may be missed.
Using the address listed in his koseki, Tsutsumitani then went to the municipal office of his parents' home about an hour away by train to apply for his father’s koseki. This contained the names of Tsutsumitani and his siblings as well as the address of his father’s previous family register from before he got married — his next lead.
“From there on, we entered unknown territory,” he says. “It was turning into quite an adventure.”
The man who connects the dots
“Jibun de Tsukureru 200-nen Kakeizu,” roughly translated as “Make Your Own 200-year-old Family Tree,” was written in 2015 by Masayuki Hashimoto, a certified administrative scrivener who specializes in creating genealogical charts. He’s been doing this for 18 years and has compiled around 1,000 family trees to date.
“Most requests come from those who are either interested in learning about their ancestors from a purely intellectual standpoint and others who want to leave such records for their descendants,” he says.
Hashimoto charges ¥77,000 for drawing up a family tree based on one surname and around ¥300,000 when it involves the lineages of both the client’s mother and father.
Additional fees emerge when he’s asked to dig even deeper beyond family registers, which often involves on-the-ground fieldwork and research into local history. He says he also receives occasional requests from Nikkei, non-Japanese of Japanese descent who live overseas and are curious about their heritage.
Typically, ancestral lineages up to the Meiji Era (1868-1912) or even the late Edo Period (1603-1867) can be traced using just the koseki, the old, invalidated koseki and joseki. As the client’s proxy, Hashimoto has these mailed to him from local government offices before drafting a pedigree chart.
In its most ancient form, the koseki can be traced back to the sixth century. Its modern incarnation, however, first appeared in 1872, soon after the Meiji Restoration, and was called the jinshin koseki. This version was far from perfect, since the format hadn’t been unified and some descriptions made it possible to single out those who had descended from Japan’s feudal outcasts, according to Takuma Aoyama, an official at the justice ministry’s koseki division. The jinshin koseki could include employees, mistresses and other sensitive information such as criminal records.
“The jinshin koseki are currently unavailable for inspection,” Aoyama says, adding that the documents are stored in strict confidence at local legal affairs bureaus.
The jinshin koseki was revised and standardized in 1886, and Hashimoto says this is the last koseki he looks for when tracking down the ancestors of his clients.
“That doesn’t mean I can always go this far back,” he says. “For example, Tokyo’s shitamachi (downtown) area was devastated by the American air raids of 1945, and many koseki have thus been destroyed.
“There were other events that led to the loss of koseki,” he adds, citing the Great Kanto Earthquake of 1923 that leveled Tokyo and took the lives of over 100,000 people, as well as the bloody Battle of Okinawa that raged on the southernmost island chain toward the end of World War II.
After gathering what relevant koseki he can, Hashimoto’s job is mostly complete. If he wants to investigate further by examining family patterns from early modern Japan, he can draw on other historical documents, including the shumon ninbetsu aratame-cho, a combination of religious investigation and local population registers, as well as the kako-cho, the death registers at Buddhist temples.
“Families of samurai and powerful village heads often submitted their lineage to the local feudal domain for record, and some old households still own their family trees,” he says. “Through these investigations, I occasionally discover that my client’s ancestors are connected to a historically relevant figure. There have also been cases where I’ve handed over the contacts of their distant relatives and a new friendship was nurtured.”
The household versus the individual
In the February 1976 issue of the monthly magazine Bungei Shunju, four members of the imperial family gathered to take part in a roundtable discussion. They touched on various topics, and at one point Prince Tomohito of Mikasa, the first cousin of Emperor Akihito, and Prince Nobuhito of Takamatsu, a younger brother of Emperor Showa, spoke candidly about the koseki system.
“I have to pay residents’ tax even despite not having a koseki,” Prince Tomohito is quoted as saying.
“It’s like having your civil rights suspended,” Prince Nobuhito replies with equal humor.
Their comments are cited in Masataka Endo’s “Koseki to Mukoseki — Nihonjin no Rinkaku,” a book that explores the history of koseki and those who have fallen through the cracks of the system.
Endo, one of the leading experts on the topic, says koseki were given to “subjects” by the emperor, and its presence — or absence — was the primary basis for separating the imperial family from the general population.
“Even today, the emperor does not have a koseki, and when a member of the royal family marries a commoner, they leave the royal family and lose their royal status, becoming a member of the general public,” he says.
Before World War II, koseki functioned as part of the ie seido (Japanese household legal structure), a social framework designed to continue over generations under which the household, family name and family business are passed on from father to the eldest son along a paternal line.
That system was abolished in 1947 under a postwar Constitution and revision to the Civil Code, where the basis for inheritance was changed from primogeniture to that of equal inheritance for all children. The household was also redefined to only constitute married couples and their unmarried children, putting a limit on the maximum number of generations under the same koseki to two.
However, there are people who, for some reason or another, have not had their births registered and are living without a family register. As of March 10, the justice ministry counted 771 such people, although there are some estimates that put the number at around 10,000.
Sometimes the problem can be attributed to social isolation or neglect, but the majority of cases stem from the century-old Civil Code’s provisions that states any child born within 300 days of a divorce shall be deemed to have been conceived during that marriage. This definition has prevented victims of domestic violence, for example, from registering their children in order to avoid contact with their former husbands.
That provision has been reformed, however, with a change that came into effect this month stipulating that if a woman is remarried at the time of birth, her current husband will be considered the child’s father.
Endo says those without a koseki can still participate in society, just as foreign residents who don’t have koseki do. As long as an individual has a certificate of residence, they can belong to national health insurance and pension plans, hold jobs and attend public schools. There are drawbacks, however — for example, such individuals are not able to obtain a Japanese passport.
“There’s a culture in Asia that places emphasis on the bloodline and family, valuing the household over the individual. And in Japan, the koseki is what records the household,” Endo says. “That sentiment has been around since ancient times and may be reflected in the newfound interest in creating family trees.”
Endo adds that the koseki system may be out of step with current realities, though, merely functioning as an archaic, moral tool that tries to define what being “Japanese” is. And with the new digital My Number ID system introduced in 2015, which focuses on individual residents of Japan, the relevance of the family register may be fading.
“The younger generation is hardly aware of their koseki, only coming in contact with them when applying for a passport or when getting married,” Endo says. “I myself really came face to face with my family’s koseki when my parents passed away and I needed them for inheritance purposes.”
“Family registers have become increasingly unfamiliar to the Japanese, and there is a stronger perception that they are a stumbling block in moving forward with issues such as separate surnames for married couples and same-sex marriages.”
There and back again
As Tsutsumitani delved deeper into his ancestry using available family registers, he began learning new aspects of his ancestral history.
“I knew my father had two other siblings, but I was shocked to find out he had another sister named Yukiko who died when she was 2 months old,” he says.
His grandfather's family register also contained the names of Tsutsumitani’s great-grandparents, whom he’d never heard of before. He also noticed how family structures reflected the social realities of the times: His great-grandfather, for example, had seven siblings, and his great-great grandfather had five. He also found old-school hentaigana, or variant kana, used in the names of family members.
As he climbed back up his lineage, his family’s registered domicile moved northward from Kyoto and up to Ishikawa Prefecture, an area unfamiliar to both Tsutsumitani and his known relatives. The final ancestor he arrived at was Satobe or Satohe, a name whose pronunciation he has yet to decipher.
Based on the dates of birth of his descendants, Tsutsumitani estimated Satobe was born before 1813. Satobe’s eldest son, Taromatsu, for example, was born on June 20, 1833, during the Tenpo Era (1830-44), which is known for a great famine.
However, the biggest surprise came when Tsutsumitani searched the Internet for the address he found on the oldest family register and stumbled upon one of the names mentioned in it. He decided to take the plunge and visit the place with his wife and son in the summer of 2016.
“We drove up north from Kanazawa and took a mountain road. We got out of the car near a place called Shinbo on the outskirts of Wajima,” he says, referring to the city known for its lacquerware that was devastated during the Jan. 1 earthquake that slammed the Noto Peninsula.
Shinbo, a district in the town of Mii, is a tiny hamlet. The family strolled through narrow paths between rice paddies and past small shrines nestled within forests until they happened upon a villager, an old woman, and explained why they were there. She knew the person they were looking for, took out her mobile phone and called him up: Sukeo Tsutsumidani, a member of the local volunteer fire department and the son of the late Sukeshichi Tsutsumidani. (Interestingly, Tsutsumitani’s relatives in Shinbo pronounce their surname with a “d” rather than a “t.”)
Sukeo invited the family to his beautifully weathered two-story home, and Tsutsumitani showed his host the family tree he had brought along. They exchanged stories about their relatives before visiting Sukeo’s family grave deep in the mountains to offer their prayers.
“It was like a revelation,” Tsutsumitani recalls. “These people I’ve been seeing on the koseki were very much real, having led their own lives, just like us.” He recently called up Sukeo, who told him that he was doing okay despite the disaster that struck the region nearly four months ago. “He said, ‘I’m in good spirits for now!’”
Did this journey into the past have any impact on Tsutsumitani’s young son?
“He’s a high-school student now. I asked him the other day whether he remembers the trip, and he said, ‘Not much,’” Tsutsumitani replies with a laugh. “In any case, I’d just like him to understand that he’s here because of the many, many ancestors who came before him.”
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