Karafuto Agency, from 1943 Karafuto Prefecture (, Karafuto-chō later 樺太県, Karafuto-ken; ), commonly known as South Sakhalin, was a colony of the Empire of Japan on Sakhalin from 1907 to 1943 and later a prefecture until 1945.
Karafuto became a territory of the Empire of Japan in 1905 after the Russo-Japanese War, when the portion of Sakhalin south of 50°N was ceded from the Russian Empire in the Treaty of Portsmouth. Karafuto was established in 1907 as an external territory, until being upgraded to an "Inner Land" of the Japanese metropole in 1943. Ōtomari (Korsakov) was the capital of Karafuto from 1905 to 1908 and Toyohara (Yuzhno-Sakhalinsk) from 1908 to 1945.
In August 1945, the Japanese administration ceased to function following the invasion of South Sakhalin by the Soviet Union. Karafuto Prefecture was de facto replaced with Sakhalin Oblast, although it continued to exist de jure under Japanese law until it was formally abolished as a legal entity by Japan in June 1949.
Name
The Japanese name Karafuto purportedly comes from Ainu (), which means "the island a god has created on the estuary (of Amur River)". It was formerly known as Kita Ezo, meaning Northern Ezo (Ezo was the former name for Hokkaido). When the Japanese administered the prefecture, Karafuto usually meant Southern Sakhalin only. For convenience, the northern part of the island was sometimes called Sagaren.
In Russian, the entire island was named Sakhalin or Saghalien. It is from Manchu sahaliyan ula angga hada, meaning "peak of the mouth of Amur River". The southern part was simply called Yuzhny Sakhalin ("South Sakhalin"). In Korean, the name is Sahallin or Hwataedo, with the latter name in use during Korea under Japanese rule.
History
Japanese settlement on Sakhalin dates to at least the Edo period. Ōtomari was established in 1679, and cartographers of the Matsumae domain mapped the island, and named it "Kita-Ezo". Japanese cartographer and explorer Mamiya Rinzō established that Sakhalin was an island through his discovery of what is now named Mamiya Strait (Strait of Tartary) in 1809. Japan unilaterally proclaimed sovereignty over the whole island in 1845.
The 1855 Treaty of Shimoda acknowledged that both the Russian Empire and Japan had joint rights of occupation to Sakhalin, without setting a definite territorial demarcation. As the island became settled in the 1860s and 1870s, this ambiguity led to increasing friction between settlers. Attempts by the Tokugawa shogunate to purchase the entire island from the Russian Empire failed, and the new Meiji government was unable to negotiate a partition of the island into separate territories. In the Treaty of Saint Petersburg (1875), Japan agreed to give up its claims on Sakhalin in exchange for undisputed ownership of the Kuril Islands.
Japan invaded Sakhalin in the final stages of the Russo-Japanese War of 1904–1905, but per the 1905 Treaty of Portsmouth was allowed to retain only the southern portion of the island below the 50° N parallel. Russia retained the northern portion, although the Japanese were awarded favorable commercial rights, including fishing and mineral extraction rights in the north. In 1907, Karafuto Prefecture was officially established, with the capital at Ōtomari. In 1908, the capital was relocated to Toyohara.
In 1920, Karafuto was officially designated an external territory of Japan, and its administration and development came under the aegis of the Ministry of Colonial Affairs. Following the Nikolaevsk Incident in 1920, Japan briefly seized the northern half of Sakhalin, and occupied it until the establishment of formal diplomatic relations with the Soviet Union in 1925; however, Japan continued to maintain petroleum and coal concessions in northern Sakhalin until 1944. In 1943, the status of Karafuto was upgraded to that of an "inner land", making it an integral part of the Empire of Japan.
As Japan was extending its influence over East Asia and the Pacific through the establishment of a Greater East Asia Co-Prosperity Sphere, the Imperial Japanese Army as part of its offensive contingency plans to invade the Soviet Union if it either became involved in the Pacific War or collapsed due to the ongoing German invasion, proposed the annexation of the remaining northern half of Sakhalin to Japan.