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14 May 2020

Lost at sea: a discovery in a Japanese koseki

As we observe Asian Pacific American Heritage Month, we share this story by guest contributor Gordon Hamachi, based on research into his Japanese heritage.

"That’s got to be a mistake," I muttered, as I puzzled over my freshly received koseki tohon.  Koseki tohon are official Japanese government records that identify all family members in a household.  According to the translation, my maternal grandparents' only child was a male named Yojiro Nishikawa, born 21 April 1930.

Family members all disagreed.  My mom is one of seven children, all born in California, starting with Hatsuko (“Grace”) in 1925.  Even if there was some unknown Japanese custom regarding the oldest son, that would be Katsumi, who was born in 1926. Phone calls confirmed what I already knew: nobody had heard of a family member named Yojiro. 

This would not be the first time a government bureaucracy had erred.  When I originally requested my family records from Japan, I was required to attach a copy of my mother’s U.S. birth certificate.  Her birth certificate is a sloppy mess, with multiple typographic errors in both her first and last names. To avoid unnecessary confusion, I silently corrected these errors with Photoshop before transmitting the birth certificate.

Because Yojiro couldn’t possibly be a relative, I promptly forgot about him as I gleefully mined the Japanese government records to add four generations of ancestors to my family tree.  It was months later when I revisited the matter of Yojiro.  This time I noticed something odd that I had missed: according to the koseki, Yojiro was "born above Pacific ocean between Honolulu, Hawaii and San Francisco, U.S." He couldn’t have been born on an airplane, as Pan American’s China Clipper didn’t begin service until 1935.  In 1930 people traveled across the Pacific by boat.

My maternal grandparents, Haruji and Tsuruye Nishikawa, from their Alien Registration cards
Fortunately, steamship records are freely available on  I was delighted to find a couple of matches for my grandmother.  One was from 17 April 1924 when—just after she married in Japan at age 18—she traveled to San Francisco on the Korea Maru.  The other was dated 11 April 1930, when my grandmother sailed on the Tenyo Maru from Yokohama, Japan to San Pedro, California with children ages five, three, and one. Presumably she had taken them to Japan to visit family. Out of curiosity I also searched for the mysterious Yojiro Nishikawa.  This led to a tragic discovery. A separate page of the passenger manifest of the Tenyo Maru recorded that my grandmother gave birth to a son, Yojiro, on 21 April 1930, about 400 miles northwest of Honolulu, followed by his death a few days later of pneumonia, not far from San Pedro.  Imagine the hardship of traveling while pregnant in a tiny third-class cabin with three small children, giving birth on the ship, and then losing the child.

Yojiro was a late addition to the passenger manifest

Only births and deaths reported to the Japanese Consulate in the U.S. make their way into the official Japanese records.  My grandparents never bothered to inform the consulate, but the steamship company doubtlessly reported births and deaths that happened at sea.  This is why Yojiro was recorded as their only child.

That is the story of how I discovered an uncle that nobody knew.

Gordon Hamachi was born in Southern California, moved to the Bay Area to study computer science, and then worked in the tech industry.  Now retired in Mountain View, he has been working on genealogy for the past five years and repairing books at CGS.  Bicycles and computers are some other things that he likes to repair: years ago he was on the board of Berkeley Neighborhood Computers, and more recently he served on the board of the Silicon Valley Bicycle Exchange.
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