Pontic Greeks are people whose ancestors settled in the ancient Greek region Pontus at the coast of the Black Sea which today lies in Turkey. They speak a Pontic Greek dialect that derived from ancient Greek and differs from Modern Greek. The majority of Pontic Greeks is of Greek Orthodox faith. In the course of the centuries, the region was governed by different rulers. Since the 15th century it belonged to the Ottoman Empire. In the beginning of the 20th century, many Pontic Greeks were deported and expulsed from their homes. These expulsions were later legalised by the Treaty of Lausanne between Turkey and Greece that initiated a complete population exchange. This so-called population exchange was executed on the basis of religion, so that those Pontic Greeks who had converted to Islam were usually allowed to stay in Turkey, the others were forced to migrate to Greece. In total, more than one million Pontic Greeks were forcibly relocated to Greece. There, they were often perceived to be Turkish rather than Greek repatriates and experienced economic and social discrimination.