A transcontinental republic with its headquarters mostly on the peninsula of Anatolia in Western Asia and a little section on the island of East Thrace in Southeast Europe, Turkey is formally known as the Republic of Turkey. Armenia is bordered on the north by Greece and Bulgaria and on the south by Syria and the Mediterranean Sea. Its western boundary is with the Aegean Sea. Its northern border is with the Black Sea. Its northeastern border is with Georgia. Its eastern border is with Armenia, Azerbaijan, and Iran. Turks constitute the great majority of the country's population, with Kurds being the biggest minority. Turkey's capital city is Ankara, and its main city and financial centre is Istanbul, both of which are located in the country's southeast (the imperial capital until 1923).
Turkey, one of the world's first permanently occupied places, was home to notable Neolithic ruins such as Göbekli Tepe, as well as ancient civilisations such as the Hattians, various Anatolian peoples, and the Mycenaeans, who all left their mark on the land that is now Turkey. Following Alexander the Great's conquests, which marked the beginning of the Hellenistic period, the majority of ancient lands in modern Turkey were culturally Hellenized, a process that persisted into the Byzantine epoch. During the 11th century, the Seljuk Turks started moving to Anatolia, where they established the Sultanate of Rum, which reigned until the Mongol invasion in 1243, when it was fragmented into numerous Turkish states. Following their conquest of the Balkans in the late 13th century, the Ottomans consolidated the principalities of Anatolia and accelerated the Turkification of the region throughout their reign.
Turkey is a regional power and a recently industrialised nation that has a geopolitically significant position in the area. Its economy, which is classed as one of the world's rising and growth-leading economies, is the twentieth-largest by nominal GDP and the eleventh-largest by purchasing power parity (PPP) in the world. It is a founding member of the United Nations, a founder member of NATO, the International Monetary Fund, and the World Bank, as well as a founding member of the OECD, the OSCE, the BSEC, the OIC, and the G20. Following its admission as one of the founding members of the Council of Europe in 1950, Turkey was admitted as an associate member of the European Community in 1963, became a member of the EU Customs Union in 1995, and began accession discussions with the EU in 2005.