This Book of Daniel starts out on a dire note, the capture of Jerusalem. However, unlike the Book of Ezekiel, there is only a vague date for the siege of Jerusalem, the 3rd year of King Jehoiakim, which would have been 606 BCE. However, there is no other indication of a siege at that time. Perhaps, this meant 598 BCE when King Jehoiakim was deposed. It is not clear who the author of this work was. However, the Judaean king fell under the power of King Nebuchadnezzar, because the Lord let it happen. Yahweh is not the term used for God in this post-exilic work. Rather the Greek Kyrios was used. The Babylonian king took some of the Temple vessels and treasures with him to Babylon, or Shinar as it is called here. He brought them to the treasury of his gods, which would have been Marduk and Nebo.
The Chaldeans dishonored their own gods. Whenever they saw a mute person, they would bring the god Bel to them. Then they would pray to Bel to make him speak, as if this false god could understand. But then they would leave him or her there with Bel with no response, because these worshipers of Bel had no sense themselves. Bel was the term used for the Babylonian god Marduk, or Lord. It also was used for many gods in the region. This may have been the start of the use of Lord for the God of Israel, Yahweh.
This oracle of Yahweh says that Jeremiah should proclaim to the various nations and not conceal the fact that Babylon was taken. However, Jeremiah died in 582 BCE and Babylon was defeated in 539 BCE, over forty years after the death of Jeremiah. Previously, Jeremiah had been very favorable to King Nebuchadnezzar of Babylon. Here he was told to set up a banner that said that Babylon with its false idol gods was put to shame and dismayed, especially two Babylonian gods, Bel and Merodach. Bel was another encompassing word for master or lord as some of the Hebrew words used about Yahweh. It also had some connection to Baal in the Mesopotamian area. Merodach or Marduk was the principal god or patron of the city of Babylon. Thus these two major Babylonian gods would be put to shame and dismayed. Much the same can be found in Isaiah, chapter 46.