In his days Nebuchadnezzar king of Babylon came up
Against Jerusalem; this was in the latter end of the third, or the beginning of the fourth of Jehoiakim's reign, and the first of Nebuchadnezzar, ( Jeremiah 25:1 ) ( 46:2 ) , when Jehoiakim was taken, but restored upon promise of subjection and obedience, and hostages given, at which time Daniel and his companions were carried captive, with some of the vessels of the temple; (See Gill on Daniel 1:1) (See Gill on Daniel 1:2)
and Jehoiakim became his servant three years:
which were the fifth, sixth, and seventh years of his reign:
then he turned and rebelled against him;
being encouraged by the king of Egypt, who promised to assist him against the king of Babylon; Nebuchadnezzar is the Nabocolasser in Ptolemy's canon; and Berosus F14 testifies, that seventy years before the Persian monarchy he made war against the Phoenicians and Jews, and it is from this time the seventy years' captivity is to be dated.
F14 Apud Clement. Alex. Stromat. 1. p. 329.