There are two men, both listed only as "S. Sakaoka," in the 1910 Federal Census for Brighton Township, Sacramento, California. Their relationship to each other is not given, as they were both hired men, living in the household of "S. Kawasaki." The younger is 18. The older man's age looks like 60, but could be 50. Shunjiro's passport said he was the oldest son, so the older man is certainly not a brother.

The older man must be Shuniro, while the younger man must be his son, Shunjiro. The older man immigrated in 1906, and it looks like the younger man immigrated in 1909. Both of these dates are consistent with other records. The younger Sakaoka's age in 1910 is also consistent with other records. According to family sources, Shunio Sakaoka went back to Japan. Indeed, he can be found in neither the 1920 nor 1930 U. S. census.

In 1924, when his son, Shunjiro, along with his wife, Hawayo, and son's Toshio and Hideo, returned to California, Shunjiro referred to his father as Seitero Sakaoka, who lived at 230 Niho Muro, Hiroshima, Japan.  Was this an alternate name for his father, Shuniro, or was this a "lost in translation" problem?

NOTE that the address book of Masako (Sakaoka) Nakamoto, Shuniro's granddaughter, included to names of possible cousins. Those two names each included a mother whose maiden name was Sakaoka. They came from two different birth families. This information, plus publicly available sources have allowed this family to be put together.

According to culturetour.net the name, Sakaoka, means "slope, incluen, hill/ meaning mount, hill or knoll."  When this site ws created, the estimated population of Sakaokas in Japan was 780.  It would also appear that Sakaoka is not among the top 5 Sakaoka populations.