Yoshida Shoin was born in 1830 in Matsumoto, a small village close to the castle town of Hagi, Choshu Domain (modern-day Yamaguchi prefecture). He was the second son of a lower ranking samurai named Sugi Yurinosuke and was adopted by his uncle Yoshida Daisuke at the age of four. Yoshida Shoin was also known by the first names Toranosuke, Torajirō, Daijirōand Matsujirō, while his samurai name was Norikata.
The process of adopting younger sons from the Sugi house was established generations before Shoin’s birth. The Sugi family controlled two additional samurai lineages - the Tamaki and the Yoshida lineages to avoid the financial problem. The oldest male became the Sugi heir and the younger Sugi sons were adopted by the Tamaki and Yoshida lines as their heirs to ensure the Sugi succession was protected this required the head of the house in the Yoshida line and most generations the Tamaki line to remain unmarried. Daisuke who at the time had problems with his health died at the age of 28, leaving Yoshida Shoin as the heir of the Yoshida lineage at five years of age.