"We may infer from this pericope as it is clearly stated in 1 Chr. 5:17 and Neh. 7:5 that Jewish families kept genealogies to prove their Jewish descent, and to ascertain that mixture with foreign groups was somehow excluded."50
Even though these people could not establish their Jewish ancestry with certainty, the leaders of the restoration permitted them to return with those who could. It is understandable that some of the Jews born in Babylon, perhaps of mixed parentage, would have had trouble tracing their genealogies.
"Dr. Nelson Glueck, in commenting on the phenomenon of historical memory as evidenced in the Old Testament, relates an experience which Mr. A. S. Kirkbride had while serving with Lawrence of Arabia' in 1917. He told me,' writes Glueck, that on one occasion, while he was in an Arab encampment, an Arab got up and related the history of his forbearers back to forty generations, and that there were others in the assembly who obviously could have done the same, telling who married and who begat whom, and where they lived, and frequently what they had done, and where they wandered. Kirkbride said it sounded exactly like a chapter of genealogy out of the Bible' (Newsletter of Nelson Glueck, Aug. 22, 1942)."51