The myth of a devastating flood sent by a deity to cleanse the world of sin is a widespread one. It is famously found in the Bible, but also in ancient Mesopotamia and Greece, medieval India, among the Maya, in North America and in Cornwall. The details vary, but in each a vast area of fertile farmland is destroyed by a huge flood sent by a god, or gods.
The fact that so many cultures have a myth about a flood has led some historians to wonder if there may have been a real event that explains the myths. We know that 18,000 years ago the world’s sea levels were about 120m lower than today due to the amount of ice trapped in glaciers. When the Ice Age ended, the glaciers melted and seas rose over a 10,000-year period to modern levels. Vast areas of land that had been inhabited by humans disappeared under the waves. However, an event that took place more than 8,000 years ago seems too remote to most historians to have been remembered in a pre-literate society.
Another idea is that the flood myths were inspired by the discovery of fossilised shellfish and other marine animals in rocks high in the mountains. The Ancient Greeks certainly thought that this ‘proved’ that the seas had once been much higher than today, though we now know that it is the rocks that have moved not the sea level.
So although a mighty flood did take place and huge swathes of land were lost to the seas, it is unlikely that a Great Flood occurred as described in the myths.