There are actually two parts to the book. The first of these, chapters 1 to 6, gives in chronological order the experiences of Daniel and his companions in government service from 617 B.C.E. to 538 B.C.E. (Dan. 1:1, 21)

The last verse of chapter 1, which may have been added long after the preceding portion was written, indicates that Daniel was still in royal service some 80 years after his going into exile, which would be in about 538 B.C.E.