Oraio was founded in the 12th century AD when its population was still Bulgarian Christian. The conversion to Islam occurred during the period 17th-18th century. Following the First Balkan War, Bulgaria took possession of Oraio in 1912, but after a period of eight months, it was taken back by the Greek army. Shortly thereafter, as part of the accords concluding the Balkan Wars, Oraio and Western Thrace were ceded to Bulgaria and remained a part of the latter until the end of World War I. Following the Bulgarian defeat in this war, Western Thrace, and thus Oraio, was given to Greece in the second half of April 1920 at San Remo conference of the prime ministers of the main allies of the Entente powers (except the US). Later in 1923, it was left to Greece with the rest of Western Thrace region by the Treaty of Lausanne. It was occupied by Bulgaria in the period 1941–1944 during World War II. Later in 1944, it was left to Greece.
In the second half of April 1920 in San Remo conference of the prime ministers of the main allies of the Entente powers (except the US) Western Thrace was given to Greece.
Source: wikipedia.org
