Lower Mesopotamia Lower Mesopotamia Lower Mesopotamia is a historical region of Iraq. Also known as the Sawad and al-'Irāq al-'Arabi ("Arabian Irāq") in the Middle Ages. Lower Mesopotamia was home to ancient Sumerian and Babylonian civilisations. An alluvial plain begins north of Baghdad and extends to the Persian Gulf. Here the Tigris and Euphrates rivers lie above the level of the plain in many places, and the whole area is a river delta interlaced by the channels of the two rivers and by irrigation canals. Intermittent lakes, fed by the rivers in flood, also characterize southeastern Iraq. A fairly large area ()
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