The eastern border of Anatolia is traditionally held to be a line between the Gulf of Alexandretta and the Black Sea, bounded by the Armenian Highland to the east and Mesopotamia to the southeast. Thus, traditionally Anatolia is the territory that comprises approximately the western two-thirds of the Asian part of Turkey. Nowadays, Anatolia is also often considered to be synonymous with Asian Turkey, which comprises almost the entire country; its eastern and southeastern borders are widely taken to be Turkey's eastern border. By some definitions, the area called the Armenian highlands lies beyond the boundary of the Anatolian plateau. The official name of this inland region is the Eastern Anatolia Region.
Following the Armenian genocide, Ottoman Armenia was renamed "Eastern Anatolia" by the newly established Turkish government. Vazken Davidian terms the expanded use of "Anatolia" to apply to territory formerly referred to as Armenia an "ahistorical imposition", and notes that a growing body of literature is uncomfortable with referring to the Ottoman East as "Eastern Anatolia". Most archeological sources consider the boundary of Anatolia to be Turkey's eastern border.