Mesopotamia incorporating not only parts of Syria but also almost all of Iraq and southeastern Turkey. The neighbouring steppes to the west of the Euphrates and the western part of the Zagros Mountains are also often included under the wider term Mesopotamia. A further distinction is usually made between Northern or Upper Mesopotamia and Southern or Lower Mesopotamia. Upper Mesopotamia, also known as the "Jazira", is the area between the Euphrates and the Tigris from their sources down to Baghdad. Lower Mesopotamia is the area from Baghdad to the Persian Gulf and includes Kuwait and parts of western Iran. In modern
Mesopotamia Empire. Around 150 BC, Mesopotamia was under the control of the Parthian Empire. Mesopotamia became a battleground between the Romans and Parthians, with western parts of Mesopotamia coming under ephemeral Roman control. In AD 226, the eastern regions of Mesopotamia fell to the Sassanid Persians. The division of Mesopotamia between Roman (Byzantine from AD 395) and Sassanid Empires lasted until the 7th century Muslim conquest of Persia of the Sasanian Empire and Muslim conquest of the Levant from Byzantines. A number of primarily neo-Assyrian and Christian native Mesopotamian states existed between the 1st century BC and 3rd century AD, including