So the priests, and the Levites, and the porters, and the singers, and some of the people, and the Nethinims, and all Israel, dwelt in their cities; and when the {i} seventh month came, the children of Israel were in their cities.

(i) Which contained part of September and part of October.

Scofield Reference Notes

Margin seventh month

i.e. October; also, Neh 8:2,14.Nehemiah 7:73 Parallel Commentaries

Influences that Gave Rise to the Priestly Laws and Histories
[Sidenote: Influences in the exile that produced written ceremonial laws] The Babylonian exile gave a great opportunity and incentive to the further development of written law. While the temple stood, the ceremonial rites and customs received constant illustration, and were transmitted directly from father to son in the priestly families. Hence, there was little need of writing them down. But when most of the priests were carried captive to Babylonia, as in 597 B.C., and ten years later the temple …
Charles Foster Kent—The Origin & Permanent Value of the Old Testament

Ezra-Nehemiah
Some of the most complicated problems in Hebrew history as well as in the literary criticism of the Old Testament gather about the books of Ezra and Nehemiah. Apart from these books, all that we know of the origin and early history of Judaism is inferential. They are our only historical sources for that period; and if in them we have, as we seem to have, authentic memoirs, fragmentary though they be, written by the two men who, more than any other, gave permanent shape and direction to Judaism, then …
John Edgar McFadyen—Introduction to the Old Testament