Charles Ellicott Commentary Daniel 1:18

"And at the end of the days which the king had appointed for bringing them in, the prince of the eunuchs brought them in before Nebuchadnezzar." — Daniel 1:18 (ASV)

At the end of the days, that is, the three years specified in Daniel 1:5. Before the conclusion of this time, it appears (Daniel 2:1), Daniel was enabled to give proof of his wisdom. (See Daniel 2:28.)