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 ()
Agriculture in ancient Mesopotamia east, rising from 200-500 m in altitude, and which are now known as Jazirah (from the Arabic, "al-jazayra", 'the island'). Thus, the rivers flow through valleys which are 1-10 km wide. The southern half of Mesopotamia, which is the part properly called Mesopotamia from a geophysical point of view, since it is where the Tigris and Euphrates flow close to one another, is a vast plain, which is 150-200 km wide and has only a very slight incline, decreasing to the south until it is nearly non-existent. This encourages the development of river braiding, sudden changes of course, and the