A 21st-century map of what was Mesopotamia shows the area divided into separate countries, including Kuwait, Iraq, Arabia, Iran, Syria and Turkey. Iraq has the largest chunk of Mesopotamia and the most land fronting the Tigris and the Euphrates Rivers, which flow into the Persian Gulf. Both rivers also go through Syria and Turkey. The earliest map of Mesopotamia, dated 3500 B.C., shows the area as just one political area with various settlements named.
The two tribes shown in Mesopotamia are the Sumerians and the Akkadians, while outside the borders are the Amorites, Assyrians, Lullubi, Guti and the Elamites. By 2500 B.C., the region consisted of Northern Mesopotamia, Akkad and Sumer. Syria, which is smaller than the country of today, was included, as was part of Anatolia, which later became Turkey.
By 1500 B.C. Mesopotamia became Babylonia, with Elam to the east and Syria to the north. Parts of the original territory were taken over by the latter two countries. By 700 B.C. the entire area was ruled by the Persian Empire, with no individual country divisions.
It wasn't until the 10th century that groups like the Hamdanids and the Buyids created borders that once again divided the landscape, at least temporarily. World War I and II helped to create the country borders that appear on the modern map.