Daniel
The context of the book of Daniel is that Judah has invaded and has been conquered. Jerusalem has been plundered (including the temple) and some Israelites have been taken into exile in Babylon. Amongst those exiled are Daniel and his three famous friends.
The book is split into two parts; the first half is stories about Daniel and his friends living in Babylon and choosing to remain faithful to God, no matter what. In the end, due to their faithfulness, they are raised up and given positions of leadership.
The second half of the book contains different prophetic dreams that Daniel receives about the future. There are many thoughts on what these dreams might mean, even now. But the main purpose of this book is to give hope to God’s people that he will rescue them even in their darkest hour.