East Thrace or Eastern Thrace, also known as Turkish Thrace or European Turkey, is the part of Turkey that is geographically a part of Southeast Europe. It accounts for 3.03% of Turkey's land area and 15% of its population. The largest city is Istanbul, which straddles the Bosporus between Europe and Asia. East Thrace is of historic importance as it is next to a major sea trade corridor and constitutes what remains of the once-vast Ottoman region of Rumelia. It is currently also of specific geostrategic importance because the sea corridor, which includes two narrow straits, provides access to the Mediterranean Sea from the Black Sea for the navies of five countries: Russia, Ukraine, Romania, Bulgaria, and Georgia. The region also serves as a future connector of existing Turkish, Bulgarian, and Greek high-speed rail networks.

Turkey, officially the Republic of Türkiye, is a country mainly in Anatolia in West Asia, with a smaller part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia, Armenia, Azerbaijan, and Iran to the east; Iraq, Syria, and the Mediterranean Sea to the south; and the Aegean Sea, Greece, and Bulgaria to the west. Turkey is home to over 85 million people; most are ethnic Turks, while ethnic Kurds are the largest ethnic minority. Officially a secular state, Turkey has a Muslim-majority population. Ankara is Turkey's capital and second-largest city; Istanbul is its largest city, and its economic and financial center, as well as the largest city in Europe. Other major cities include İzmir, Bursa and Antalya.