The past few centuries1)http://www.timemaps.com/history/iraq-1000bc have seen the rise and fall of great Mesopotamian empires, first Assyria, and then Babylon. With the recent conquest of the Babylonian empire by Persians,2)http://www.timemaps.com/history/middle-east-500bc however, the people of Mesopotamia now find themselves ruled from outside the region for the first time in their long history.
The Assyrian and Babylonian policy of uprooting conquered peoples from their homelands and moving them to other areas has caused massive population upheaval. This has led to the decline of local languages and the rise of Aramaic as the lingua franca of Mesopotamia. This in turn has led to the spread of the Aramaic alphabet.
These developments make international trade easier, as do the generally high level of Persian rule and the great Persian-built roads which now span the region. Whereas the Assyrian and Babylonian periods were times of economic depression for most areas outside the imperial cores (at least, the Archaeological record suggests so), the Persian period is one of prosperity for Mesopotamia.
ORIGINAL SOURCE: timemaps.com