Thrace Europe. The word "Thrace" was established by the Greeks for referring to the Thracian tribes, from ancient Greek Thrake (Θρᾴκη), descending from "Thrāix" (Θρᾷξ). The name of the continent Europe first referred to Thrace proper, prior to extending its meaning to the whole continent. The region could have been named after the principal river there, Hebros, possibly from the Indo-European "arg" "white river" (the opposite of Vardar, meaning "black river"), . According to an alternative theory, Hebros means "goat" in Thracian. In Turkey, it is commonly referred to as "Rumeli", "Land of the Romans", owing to this region being the
Geography of Turkey of the sizable Greek-speaking community of western Turkey were forced to resettle in Greece, while the majority of the Turkish-speaking residents of Thrace who were not forced out during the Balkan wars were removed to Turkey. The boundary with Bulgaria was confirmed by the Treaty of Lausanne (1923). Since 1991 the more than boundary with the former Soviet Union, which was defined in the 1921 Treaty of Moscow (1921) and Treaty of Kars, has formed Turkey's borders with the independent countries of Armenia, Azerbaijan, and Georgia. The boundary with Iran was confirmed by the Treaty of Kasr-ı Şirin in 1639.