Toponym
The name Baghdad is pre-Islamic and its origins are unclear, but it is related to previous settlements, which did not have any political or commercial power. The name has been found as Baghdadu on Assyrian cuneiform records of the 9th century BC, and on Babylonian bricks bearing the Royal Seal of King Nebuchadnezzar (6th century BC).
When the Abbasid caliph al-Mansur founded a completely new city for his capital, he chose the name Madinat al-Salaam or "City of Peace". This was the official name on coins, weights, and other official usage, although the common people continued to use the old name. By the 11th century, "Baghdad" became almost the exclusive name for the world-renowned metropolis.
There are several rival theories as to the etymology of the specific name Baghdad. The most widely accepted among these is that the name is a Middle Persian compound of Bag "god" + dād "given", translating to "God-given" or "God's gift", from which comes Modern Persian Baɣdād. This in turn can be traced to Old Persian. A less probable guess is the Persian compound Bāğ "garden" + dād "fair", translating to "The fair garden".
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