I recommend that all those wishing to learn about the historical context of the Bible’s revelation/composition should read ‘Babylon’ by Paul Kriwaczek. Whilst his primary aim is to relate the history of Mesopotamia, and not the Bible, there is nonetheless some interesting information here which can tell us about the the intentions of Biblical authors.
The famous Sumerian Kings list for example, though presented as history, was written not to tell a literal chronology of human history, but to give King Utu-Hegal, who had driven ought the Gutians from Sumer, authority, as the descendent of Ancient Kings of Old, historical accuracy was not the aim of the game. “For some narratives, accuracy and truth are not an issue”, as Kriwaczek says.
With this in mind, did the writer of Genesis really believe in a global flood? Did he really believe in one language before Babel? Maybe he did, but this doesn’t mean it really happened, for historical accuracy was not the main aim of ancient historiography, but rather the ‘meaning of history’ was.