early humans outside the African continent; and the Dmanisi skulls are the five oldest hominins ever found outside Africa. Antiquity Kura–Araxes culture from about 4000 BC until about 2000 BC enveloped a vast area approximately 1,000 km by 500 km, and mostly encompassed, on modern-day territories, the Southern Caucasus (except western Georgia), northwestern Iran, the northeastern Caucasus, eastern Turkey, and as far as Syria. Under Ashurbanipal (669–627 BC), the boundaries of the Assyrian Empire reached as far as the Caucasus Mountains. Later ancient kingdoms of the region included Armenia, Albania, Colchis and Iberia, among others. These kingdoms were later incorporated into various Iranian empires, including Media, the Achaemenid Empire, Parthia, and the Sassanid Empire, who would altogether rule the Caucasus for many hundreds of years. In 95–55 BC, under the reign of Armenian king Tigranes the Great, the Kingdom of Armenia included Kingdom of Armenia, vassals Iberia, Albania, Parthia, Atropatene, Mesopotamia, Cappadocia, Cilicia, Syria, Nabataean kingdom, and Judea. By the time of the first century BC, Zoroastrianism had become the dominant religion of the region; however, the region would go through two other religious transformations. Owing to the strong rivalry between Persia and Rome, and later Byzantium. The Romans first arrived in the region in the 1st century BC with the annexation of the kingdom of Colchis, which was later turned into the province of Lazicum. The next 600 years was marked by a conflict between Rome and Sassanid Empire for the control of the region. In western Georgia the eastern Roman rule lasted until the Middle Ages. Middle Ages As the Arsacid dynasty of Armenia (an eponymous branch of the Arsacid dynasty of Parthia) was the first nation to adopt Christianity as state religion (in 301 AD), and Caucasian Albania and Georgia had become Christian entities, Christianity began to overtake Zoroastrianism and pagan beliefs. With the Muslim conquest of Persia, large parts of the region came under the rule of the Arabs, and Islam penetrated into the region. In the 10th century, the Alans (proto-Ossetians) founded the Kingdom of Alania, that flourished in the Northern Caucasus, roughly in the location of latter-day Circassia and modern North Ossetia–Alania, until its destruction by the Mongol invasion in 1238–39. During the Middle Ages Bagratid Armenia, Kingdom of Tashir-Dzoraget, Kingdom of Syunik and Principality of Khachen organized local Armenian population facing multiple threats after the fall of antique Kingdom of Armenia. Caucasian Albania