Daniel 5:29

‘Then Belshazzar commanded and they clothed Daniel with purple, and put a chain of gold about his neck, and made proclamation concerning him that he should be the third ruler of the kingdom.'

Belshazzar was faithful to his oath. He gave Daniel all the honours that he had promised, and his status was proclaimed within the banqueting hall where were gathered the leading lords of the realm, together with the wise men called earlier. He probably did not realise quite how soon the prophecy would be fulfilled, for while Belshazzar and his lords sang on, celebrating Daniel's appointment as men will, Cyrus' general Ugbaru was unknown to them diverting the river Euphrates that ran through Babylon into an ancient lake, so that his soldiers could enter the city along the partly dried up river bed. The city was taken almost without a fight. The Persians were in fact probably welcomed by the priests of Marduk who were sick and tired of their god being largely ignored, and the people woke up to find them in charge of the city.