Koryo-saram (고려사람; Корё сарам; Корьо-сарам; Uzbek: Корё-сарам / Koryo-saram) is the name which ethnic Koreans in the post-Soviet states use to refer to themselves. The term is composed of two Korean words: "Koryo", a historical name for Korea, and "saram", meaning "person" or "people". Approximately 500,000 ethnic Koreans reside in the former Soviet Union, primarily in the now-independent states of Central Asia. There are also large Korean communities in Southern Russia (around Volgograd), Russian Far East (around Vladivostok), the Caucasus and southern Ukraine. These communities can be traced back to the Koreans who were living in the Russian Far East during the late 19th century. There is also a separate ethnic Korean community on the island of Sakhalin, typically referred to as Sakhalin Koreans. Some may identify as Koryo-saram, but many do not. Unlike the communities on the Russian mainland primarily descended from Koreans who arrived in the late 19th century and early 20th century, the ancestors of the Sakhalin Koreans were immigrants from Japanese Korea — mostly from the southern provinces, namely North Gyeongsang Province, South Gyeongsang Province, North Jeolla Province, and South Jeolla Province — in the late 1930s and early 1940s. They were forced into service by the Japanese government to work in coal mines in what was then Karafuto Prefecture, in order to fill labor shortages caused by the Pacific War. The word Koryo in "Koryo-saram" originated from the name of the Goryeo (Koryŏ) Dynasty from which "Korea" was also derived. The name Soviet Korean was also used, more frequently before the collapse of the Soviet Union. Russians may also lump Koryo-saram under the general label koreytsy (корейцы); however, this usage makes no distinctions between ethnic Koreans of the local nationality and the Korean nationals (citizens of North Korea or South Korea). In Standard Korean, the term "Koryo-saram" is typically used to refer to historical figures from the Goryeo dynasty; to avoid ambiguity, Korean speakers use a word Goryeoin (고려인, Hanja: 高麗人, meaning the same as "Koryo-saram") to refer to ethnic Koreans in the post-Soviet states.