This description of the Book of Nehemiah is from Easton's Bible Dictionary.
Nehemiah, Book of: The author of this book was no doubt Nehemiah himself. There are portions of the book written in the first person (Nehemiah 1:1-7:73; 12:27-47, and 13:1-31). But there are also portions of it in which Nehemiah is spoken of in the third person (Nehemiah 8:1 - 10:39). It is supposed that these portions may have been written by Ezra; of this, however, there is no distinct evidence. These portions had their place assigned them in the book, there can be no doubt, by Nehemiah. He was the responsible author of the whole book, with the exception of Nehemiah 12:11,22,23.
The date at which the book was written was probably about B.C. 431-430, when Nehemiah had returned the second time to Jerusalem after his visit to Persia.
The book, which may historically be regarded as a continuation of the book of Ezra, consists of four parts.
This book closes the history of the Old Testament. Malachi the prophet was contemporary with Nehemiah.