The causes of the extinction of the Japanese wolf (Canis lupus hodophilax), once found in three-Honshu, Shikoku, and Kyushu-of the four Japanese large islands, were documented by surveying official documents of northeastern Honshu from the Meiji era (1868-1912). The results showed many instances of nuisance killings of the animals, motivated by attacks on free-ranging livestock by the animals. The extirpation policies and their implemental measures were planned and authorized by the prefectural administrations of Aomori, Iwate, Iwai (then occupying parts of both present-day Iwate and Miyagi Prefectures), and Miyagi. In Aomori Prefecture, the police killed wolves. In Iwai Prefecture, the police commanded hunters to conduct the nuisance killings. The government of Iwate Prefecture enacted a bounty system in 1875, and 201 wolves were killed in 6 years. The government of Miyagi Prefecture followed it in 1877. In Fukushima Prefecture, local people conducted nuisance killings. Besides, the documents showed that fur, meat, and other parts of wolves were traded and used in northeastern Honshu. Thus, it can be concluded that the nuisance killings and hunting of wolves in the late 19th century contributed to the extinction of these animals in northeastern Honshu.