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 used throughout the Greek Septuagint (c. 250 BC) to translate the Hebrew and Aramaic equivalent "Naharaim". An even earlier Greek usage of the name "Mesopotamia" is evident from "The Anabasis of Alexander", which was written in the late 2nd century AD, but specifically refers to sources from the time of Alexander the Great. In the "Anabasis", Mesopotamia was used to designate the land east of the Euphrates in north Syria. The Aramaic term "biritum/birit narim" corresponded to a similar geographical concept. Later, the term Mesopotamia was more generally applied to all the lands between the Euphrates and the Tigris, thereby