Artsakh (Armenian: Արցախ, romanized: Artsʻakh, pronounced [ɑɾˈtsʰɑχ]) was the tenth province (nahang) of the Kingdom of Armenia from c. 189 BC until 387 AD and afterwards made part of the Caucasian Albania, a subject principality of the Sasanian Empire, following the Peace of Acilisene.

[3][4][5][6][a] When speaking about Armenia in his Geography, the classical historian Strabo refers to an Armenian region which he calls "Orchistene", which is also believed to be a rendering of the name Artsakh.

[6] To its east and southeast laid the lowlands between the Kura and Arax rivers and the Mughan plain, which at one point formed the Paytakaran province of Armenia.

[6] Artsakh's two largest rivers were the Gargar and the Tartar (Trtu in Classical Armenian sources), which flow eastward and eventually join the Kura.

[22] The medieval Kingdom of Artsakh (1000–1261) encompassed the entire territory of the classical province and also included Gardman-Parisos to the north and the cantons of Sodk and Gegharkunik of Syunik, located on the shores of Lake Sevan.

[23] Important places in Artsakh (mostly fortified towns) included Parisos, Tigranakert, Sodk, Tsar, Vaykunik, Asteghblur, Goroz and Berdaglukh.

By the 9th century it comprised a number of small political units ruled by the Aranshahiks,[28] including the principalities of Khachen in the center and Dizak in the south.

[34][36] It is worth noting that Strabo described Armenia (which then included also Artsakh and Utik) in the 1st century BC as "monolingual",[8] though this does not necessarily mean that its population consisted exclusively of ethnic Armenians.

[37] In Robert Hewsen's view, until the 6th–5th centuries BC the proto-Armenians lived only in the western half of the Armenian Plateau (in areas between Cappadocia, the Tigris, the Euphrates, and Lake Van) and came to Artsakh and adjacent regions such as Syunik and Utik somewhat later than the central parts of the Armenian Plateau (as late as the 2nd century BC, as a result of Artaxias I's conquests).

[34] While genetical studies claimed and proved that Artsakh also was part of the original proto-Armenian homeland, and that Armenians are the direct descendants of the peoples living in the region 7800 years ago.

[34][41] In 1968, Soviet archaeologists discovered a fragment of a jawbone of a pre-Homo sapiens human dating back possibly to the Middle Acheulean culture in a cave complex near the village of Azokh in modern-day Nagorno-Karabakh.

[46] Other sites of archaeological interest are located in the vicinity of Stepanakert, Khojaly, and Astghashen, where ancient burial mounds containing human and animal remains, tools, pottery and other objects have been discovered.

[47] In general, archaeological remains in Artsakh reflect the competing influences from around 800 BC of the neighboring rival states of Urartu, Assyria, and Mannai.

[50][51] In the words of the historian Leo, judging from the Classical Armenian sources, Artsakh, along with Syunik, Utik, Sasun and other remote regions of Greater Armenia, was regarded as a "wild" or "barbarous" province when compared with the center of the kingdom, Ayrarat.

In 310 St Grigoris, the grandson of Grigor the Illuminator, was ordained bishop of Iberia and Caucasian Albania in the monastery of Amaras, being just 15 years old at the time.

[54] After his martyrdom by the Mazkutian king on the field of Vatnean (near Derbent), his disciples conveyed his body back to Artsakh and buried him in Amaras, which had been built by Gregory the Illuminator and Grigoris himself.

Caucasian Albania, as an ally of the Sassanids at the time, gained Armenian territories the right bank of the river Kura up to the Arax, including Artsakh, Gardman and Utik.

In the early 9th century two Armenian princes, Sahl Smbatian and Esayi Abu-Muse, revolted against Arab rule and established two independent principalities in Artsakh: Khachen and Dizak.

[65] The latter 28 times unsuccessfully attempted to conquer Ktich Castle (situated near modern-day Togh in Nagorno-Karabakh), the main stronghold of the Armenians of Artsakh.