Sakhalin is the largest island of Russia in the Pacific Ocean. Its population in 2019 amounted to 489 thousand people. Mainly it is represented by ethnic Russians, and also by a small Korean community and indigenous people – Ainus, Oroks and Nivkhs.
Before the middle of the XIX century, Sakhalin had been mainly under Chinese control, however by the end of the century the island was divided between the Russian Empire and Japan. At the same time Sakhalin turned into a place for exiles and hard labor camps.
After WWII, following the Japanese defeat, the entire island became the territory of the Soviet Union (just like the Kuril islands). Most of the Ainus moved to Hokkaido.