evidence: Karafuto, also known as Sakhalin, is an island located in the North Pacific Ocean, and it is currently divided between Russia and Japan. After World War II, the Soviet Union gained control of the northern part of the island, while Japan lost its territorial claims to the southern part.Is Karafuto part of Japan? 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.Does Japan still claim Sakhalin? [...] Karafuto is the Japanese name for the southern part of Sakhalin Island, which is located north of. Hokkaido, Japan. Although the island is now governed by the Russian Federation, the southern part, below the 50th parallel north, belonged to the Japanese Empire from 1905 to 1945.Who controls Sakhalin Island?