I believe it had to do with the 'wise men from the east'. A number of anthropologists believe the early Sumerians (the ones we know about) were in fact refugees from the Ice Age flooding of Sundaland, they would have brought a number of 'foreign' languages and possibly their flood stories with them. Some DNA and disease studies offer some support for these theories.
Voyages of the Pyramid Builders
Is this a recent book?