5:30 In that night. While the Babylonians were feasting, the Persians had entered the city through the channel of the Euphrates River, which they had diverted, and caught them completely unprepared, confident that their great walls could not be breached. This was about 539 B.C.

5:31 Darius. Darius the Mede has been identified as the general, Gobryas, who was then “made king over the realm of the Chaldeans” (Daniel 9:1) by the Persian emperor Cyrus (Daniel 10:1).