"If you read texts predating the Bible, you'll find that the well-known Old Testament Noah did not make his literary debut in the Holy Scriptures. Rather, he made his first appearance about 2,000 years or so earlier in the Sumerian civilization of Mesopotamia. Holding power from roughly 3500 B.C. to 2000 B.C., the Sumerians were the first people to sketch out the story of Noah, except they called him Ziusudra.
Later, the Babylonians would record a similar tale in the Epic of Gilgamesh, the oldest book in recorded history. As the Babylonians tell it, a man named Utnapishtim was warned of a great storm and built a boat an acre in size, split into six different divisions. All surrounding lands flooded after six days and nights of rain. Sailing to what may have been modern-day Bahrain [source: Discovery Channel and BBC], Utnapishtim and his wife received immortality for his obedience.
Here's where the Tigris and Euphrates rivers come into play. The two waterways that slice through modern day Iraq served as the main thoroughfares for trade at that time, and were the setting for the flood story in the Epic of Gilgamesh. Because both rivers flood each summer, scholars think that Noah's story may be based on that actual event -- a greater than usual flooding of the Tigris or Euphrates. In fact, archeologists have uncovered evidence of such a great flood in Mesopotamia, dating back to around 2900 B.C., that quickly wiped out a number of Sumerian cities [source: Saggs]."
For the whole subject and more the source is: http://history.howstuffworks.com/asian- ... /printable
