Although there are possible influences, I would not describe it as a simple retelling. Every culture builds on the one before. Even if it is a retelling, there is no saying that they were not actually describing the same historical event from different perspectives.
It is very interesting how many of these archetypal stories are reflected in other religions and other cultures, as editors have noted here. How to proceed is to focus on how accounts differ, considering the role of "God" or of the deity, the role of man and what is said and how they relate. Comparing the accounts this way allow us to discover the different nuances the authors are trying to show.
There are also Greek and Indian versions of the Flood myth, also with narratives describing survivors on a ship. The Indian version also has some resonances with the Babylonian, as it also relates to stories about immortality. For that matter, between the story of Noah and the Garden of Eden, Genesis has both major elements of the Babylonian Flood narrative: the survivor, and plants that if eaten lead to immortality.
There has been speculation that these Flood myths might have an origin in flooding that occurred when the Mediterranean broke into the Black Sea c.6th millennium BCE. But there has also been some disputation that such flooding even occurred.
There are many ways to look at this. The first post does a good job about possible theories, but there is one that is forgotten. If the story of the flood reflects an actual flood, then the two stories can reflect an actual event. This may explain other flood stories as well - the Roman story of the flood in Ovid. In this way, one does not have to posit a common source or borrowing. Also this approach also accounts for the variations that exist between the sources. Otherwise, one will have to answer a host of questions of why one source took only certain things from another source and not others.
While the Epic of Gilgamesh was written first, there is no way of knowing whether the flood story in Genesis is simply a retelling of the Gilgamesh flood. There are said to be three possiblities:
- They are both taken from some common source
- Genesis is copied from Gilgamesh
- Gilgamesh is copied from some prior Hebrew source
The stories are so similar that it is believed that they could not have arisen independently.
Just because of the timing of the two stories (with Gilgamesh coming first) the second of these options is widely considered to be the more likely.
For example 'The Tower of Babel' is probably The Tower of Babylon, a very high, long tower built in Babylon (near modern Baghdad) by the Babylonians. Babylon was a major major city in the middle east in early biblical times.
The Jews, who wrote the Old Testament, were a small, powerless tribe surronded by big tribes and empires. First, they were enslaved by the Egyptians. Then, after their settlement in 'The Holy Land' many of them were enslaved by the Persians and shunted off to Babylon as slaves. (The Persians had conquered all of "Arabia" including Babylon)
So the Old testament is full of Egyptian references and Persian/Babylonian references, including Gilgamesh, which the Jews transformed into the story of Noah.
Stories travel. The Muslims also have the same story of Noah in the Koran. They call him Nuh.
I am able to see why one would ask the question of the relationship between the Old Testament story of Noah and the Flood and Tablet 9 in the Epic of Gilgamesh. The Epic of Gilgamesh is an ancient poem from Iraq. It is believed to be made up of various legends and myths. In the Epic Gilgamesh has lost his best friend who was killed. He goes on a journey to visit Utnapishtim and his wife. They were the only two human beings to have survived a great flood. Because of their goodness they have been given immortality. In the Old Testament version of Noah he survived with his wife and children. Noah lived to a very old age but did not have immortality. The Torah, Jewish scripture, there is even less of a correlation. The things that happen in the Epic are much more out of proportion than the bible. However, it is easy to see why they could be parallelled.