Maybe biblical history, but I question this could be called real history as in what year was that that great flood?
I agree. It's not reasonable to take literally the story of Noah's flood. That doesn't bother most religious people. The story is one that few people would want to take literally.
A liberal Rabbi once said, "Sometimes, the nicest thing you can say about God is that he doesn't exist." He wasn't being mean-spirited. He was just pointing out that a God who killed all but a handful of animals and people on earth doesn't exist. And all the people said Amen!