Japanese adult adoption

Japanese adult adoption is the practice in Japan of legally and socially accepting a nonconsanguineal adult into an offspring role of a family. The centuries-old practice was developed as a mechanism for families to extend their family name, estate and ancestry without an unwieldy reliance on blood lines. Still common today, adult adoption is a dynamic tool for social and economic mobility.

There is evidence that this practice began as early as sometime in the 13th century within the sect of Buddhism known as Pure Land Buddhism, but only really became widely used in the Tokugawa (or Edo) period, which began around 1600 and lasted until 1868. During the Tokugawa period, much of the Samurai class would adopt sons for the purpose of creating a strong, fixed position in society through the assumption of positions such as the head of household and the head of the business. It also was a way for households lacking in sons to continue a patrilineal line, and remain a functioning societal power. This was its most common purpose, but was also seen by the adoptees as a way to climb the social ladder by leaving the title of second son, etc. behind.

Though it may have originated earlier, adult adoption was used within the sect of Pure Land Buddhism. This sect of Buddhism, called Jodo Shinshu, is associated with the Honganji temples located near Kyoto. Sons associated with the Honganji would be adopted out into prominent families of the surrounding areas. It most likely developed as a strategy for gaining power within the community, but it just happened to have some practical consequences associated with it. When families would find themselves lacking either a capable male heir or a son altogether, they would turn to adoption by marrying a man to one of their daughters, or just merely taking them into their household. It was a way for families to ensure the continuity of a reliable male line that would take over as the family head and sometimes the head of the family business.

Adult adoption lost some of its steam during the following years after its use in the 13th century. It really became a common occurrence around 1600 when the Tokugawa period began. Starting out small, it was used mostly by the Samurai class, especially those who lacked an elder or a capable son. Those who wished to adopt were encouraged to look within their own extended family for suitable candidates, but would adopt outside of the family if there were no viable options. Adopted sons (during the Tokugawa period, especially in the early years) usually were a part of the same social circle and income level. From the point of view of the adopted son, it was not so much an increase of class position, but rather a way to receive an independent life by becoming a first-born son. This does not mean that there were no vertical jumps in the social stratum by less wealthy individuals, but it was significantly less common. By being adopted, second-born sons were able to take over as the heads of households, and become the leader of the family business as well as a leader within the community itself.

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