Koseki

A koseki (^?) is a Japanese family registry. Japanese law requires all Japanese households (ie) to report births, acknowledgements of paternity, adoptions, disruptions of adoptions, deaths, marriages and divorces of Japanese citizens to their local authority, which compiles such records encompassing all Japanese citizens within their jurisdiction. Marriages, adoptions and acknowledgements of paternity become legally effective only when such events are recorded in the koseki. Births and deaths become legally effective as they happen, but such events must be filed by family members.

A typical koseki has one page for the household's parents and their first two children: additional children are recorded on additional pages. Any changes to this information have to be sealed by an official registrar.

The following items are recorded in the koseki. (Law of Family Register, (戸籍法), article 13.)

Introduced in the 6th century, the original population census in Japan was called the kōgo no nen jaku (庚午年籍^?) or the kōin no nen jaku (庚寅年籍^?). This census was introduced under the ritsuryō system of governance. During the Bakufu, there were four major forms of population registration: the ninbetsuchō (人別帳^?) (Registry of Human Categories), the shūmon jinbetsu aratamechō (宗門人別改帳^?) (Religious Inquisition Registry) also called the shūmon aratamechō, the gonin gumichō (五人組帳^?) (Five Household Registry) and the kakochō (過去帳^?) (Death Registry). The shūmon jinbetsu aratamechō was created around 1670 and lasted almost 200 years. It combined social and religious registration, and data was renewed annually. Several categories of outcasts were not registered at all under this system, or were registered in specific registers, for instance the burakumin. The modern koseki, encompassing all of Japan's citizenry, appeared in 1872, immediately following the Meiji Restoration. This was the first time in history that all Japanese people were required to have family names as well as given names. Although all previous social categories were abolished and almost all Japanese people were recorded as heimin (commoners), some minorities became labelled as "new commoner" or "original eta" (shinheimin or motoeta), and discrimination went on. Problems also happened at the edge of the national territory, for instance in the Ogasawara Islands.

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