About Koseki Roots

Koseki Roots is run from Chiba, Japan, by Mitsuru Otaka (大高 充; OTAKA Mitsuru in Japanese order).

My family is from Akita, in northern Japan. I am the eldest son, and in Japan the eldest son traditionally stays to carry on the family home and look after the family graves. In my generation, I was the one who moved away. I moved to Chiba, near Tokyo. Once I was gone, I found myself thinking more and more about the place we came from.

So I went looking. I read old koseki that are no longer in use (see our glossary), temple records and local histories. Along the way, I learned to read handwritten Meiji-era (1868–1912) registers and old village documents. That kind of writing takes practice, even for Japanese readers.

I only moved a few hours away. For Nikkei families, whose ancestors crossed an ocean, that feeling must be much stronger. Many ask the same question I did: where exactly did we come from, and who were they? The answers are usually there, in Japanese: a koseki, a village history, a temple's records. Someone in Japan just needs to read them.

That is why I started Koseki Roots: to read those records here in Japan, and to bring you the story of the village your family left, in English.

Before all this, I spent 38 years as an engineer at IBM Japan. I maintained large mainframe computers for business customers and taught that work to other engineers at IBM's training center. Those years taught me to check every detail and to explain complicated things plainly. Reading an old koseki and writing it up for you takes both.

Koseki Roots is the English-language service of Tsuzuri (綴, "to bind together" or "to write down"), our family history service for families in Japan. Both use the same mark, shown at the top of this page. Elsewhere on this site, Japanese names are written surname first, as in Japan.

How we work

• Read in Japan, by someone who reads Japanese as a first language. Every register and record is read in Japanese, checked against the original image, and only then written up in English.
• Honest about uncertainty. When handwriting is ambiguous or a link between records is not proven, we say so plainly and show our confidence.
• Sources you can check. In the report we deliver to you, the notes name every book and record we used and where it is held. In our public samples, these details are withheld and only the type of source is given.
• Email only. All communication is by email, so you have everything in writing and can share it with your family.
• Your family's privacy. Your documents are used only for your order and are never published.

What we don't do

We do not file requests to Japanese government offices for you; under Japanese law that is work for a licensed administrative scrivener (gyōseishoshi). We explain how to request your family's koseki yourself. Our reports are for family history and are not certified translations.