The Armenian Highlands (Armenian: Հայկական լեռնաշխարհ, romanized: Haykakan leṙnašxarh; also known as the Armenian Upland, Armenian plateau, Armenian tableland or simply Armenia) is the most central and the highest of the three plateaus that together form the northern sector of Western Asia. Clockwise starting from the west, the Armenian Highlands is bounded by the Anatolian plateau, the Caucasus, the Kura-Aras lowlands, the Iranian Plateau, and Mesopotamia (or Fertile Crescent). The highlands are divided into western and eastern regions, defined by the Ararat Valley where Mount Ararat is located. Western Armenia is nowadays referred to as eastern Anatolia, and Eastern Armenia as the Lesser Caucasus or Caucasus Minor, and historically Anti-Caucasus, meaning "opposite the Caucasus".
During the Iron Age, the region was known by variations of the name Ararat (Urartu, Uruatri, Urashtu). Later, the Highlands were known as Armenia Major, a central region to the history of Armenians, and one of the four geopolitical regions associated with Armenians, the other three being Armenia Minor, Sophene, and Commagene.
The population of the region has been primarily Armenian for the majority of its known history. Prior to the appearance of nominally Armenian people in historical records, historians have hypothesized that the region must have been home to various ethnic groups who became homogenous when the Armenian language came to prominence. The population of the Armenian Highlands seem to have had a high level of regional genetic continuity for over 6,000 years. Recent studies have shown that the Armenian people are indigenous to the Armenian Highlands and form a distinct genetic isolate in the region. The region was also inhabited during Antiquity by minorities such as Assyrians, Georgians, Greeks, Jews, and Iranians. During the Middle Ages, Arabs and particularly Turkmens and Kurds settled in large numbers in the Armenian Highlands. The Christian population of the western half of the region was exterminated during the Armenian Genocide of 1915, and on a smaller scale, the Assyrian and Greek Genocides. Today, the eastern half is mainly inhabited by Armenians, Azerbaijanis, and Georgians, while the western half is mainly inhabited by Azerbaijanis, Kurds (including Yazidis), Turks, and Zazas, with a minority of Assyrians.
The region was administered for the majority of its known history by Armenian nobility and states, whether it was as part of a fully independent Armenian state, as vassals, or as part of a foreign state. Since the 1040s, the highlands have been under the rule of various Turkic peoples and the Safavid dynasty, with pockets of Armenian autonomy in places such as Artsakh. Much of Eastern Armenia, which had been ruled by the Safavids from the 16th century, became part of the Russian Empire in 1828 and was later incorporated into the Soviet Union, while much of Western Armenia was under the rule of the Ottoman Empire and later incorporated into Turkey. Today, the region is divided between Turkey, Georgia, Armenia, Azerbaijan, and Iran.