Note: there are links to Wikipedia articles about some of the topics that I gloss over that may be unfamiliar
Sources
The Navarre Bible: Major Prophets — The Interpreter’s One-Volume Commentary on the Bible — The Oxford Jewish Study Bible — The Companion Bible — The Scofield Reference Bible — Zondervan NASB Study Bible — Study Bible: The New Student Bible (RSV)

An icon of the prophet Daniel.
The book of Daniel is a series of visions, stories, and prophecies by the prophet. They take place during the Babylonian captivity of the Jews in the 6th century BC.
Throughout the book Daniel and his friends refuse to deny and blaspheme their Jewish faith. They are then punished in various ways (fiery furnace, lion’s den, etc.) but are never hurt, which forces the kings that attempt to punish them to acknowledge the God of Israel and worship Him.
Another major part of the book is Daniel’s visions of the future. He uses beautiful, complex imagery to lay out the history of the Babylonian kings and the various kings and kingdoms that come after them, all the way up to the time right before the Maccabean revolt of 164 BC.
There are two main interpretations of the book of Daniel. The most widely recognized, both by Catholic and non-Christian scholars alike, is that it was written not during the Babylonian Exile but right before the Maccabean revolt. Evidence includes the inclusion of words that weren’t used until after the exile, historical inaccuracies, and other seemingly conclusive points (see Navarre, Interpreter’s, JSB). According to this view a pious Jew wrote under the name of the renowned prophet Daniel (and collected traditions that had been circulating in his name) to create the book we have today.
The alternative, more mysterious view is that it was actually written by Daniel around the time of the Babylonian exile. In this case the prophecies of the book actually predict the future. Zondervan and the Companion Bible are hostile to the commonly held interpretation of authorship around 164 BC, claiming that it is only fashionable because of the contemporary anti-supernaturalist worldview that the future cannot be predicted. To them, not only does Daniel predict the future of the Jewish people after the exile, he even predicts the coming of Christ and events that still haven’t happened yet that will lead to the end of the world.

Painting of the famous story of Daniel in the lion’s den.
I’m still sort of on the fence, as there are some interesting loose ends that cannot be tied up by the proponents of the more popular view. Daniel is written in three languages – Hebrew, Aramaic, and Greek. Both Interpreter’s and Nevarre Bible admit that there is no conclusive interpretation as to why this is the case. I guess those who hold the other view don’t have any better explanation, but this proves to me that there may be more to Daniel than meets the eye.
The most convincing piece of evidence of the fringe view is their claim that scholars have what kingdoms Daniel is talking about wrong. According to the scholarly view they are Babylonian, Persian, Mede, and Greek. The alternate view supposes that these kingdoms are the Babylonain, Persian-Mede, Greek, and Roman (significant because anything about Rome would have to be Daniel predicting the future, even if he wrote in 164 BC). If this is true then the supposed historical inaccuracies in Daniel may actually be accurate, they’re just talking about different kingdoms than the scholars are looking for. If this is the case there’s even the chance that Daniel records the history of kings that are lost to time except from their references in this book.
While the fringe view has some interesting points – it certainly intrigues me – I’m more inclined to believe the widely accepted view. It doesn’t help that almost every person who believes in the fringe view uses Daniel in conjunction with the book of Revelation in ways that I know the book of Revelation is not trying to do (that is, predict anything concrete about the future other than the fact that God wins). If there were mainline scholars, Catholic or Protestant or otherwise, that believed this about Daniel then I’d be more inclined to believe it.
The main points of the book, regardless of authorship, are the most important part about it anyway. The biggest overall point, somewhat ironically considering how the fringe view sees things, is very much like the main point of the book of Revelation: that God wins in the end. God will destroy every evil. In the end every tongue will confess, and every knee will bow, to God. No matter how bleak things may look, no matter how often kings and the world seems to “win,” no matter what persecution God’s people have to endure, God will always be victorious. Those who are faithful to Him will receive glory, honor, and eternal life.
In Daniel those who deny God even in this life bow down and worship Him because of his miraculous signs, while in Revelation this is something that will happen in the future. These stories in Daniel emphasize the message that even the evil rulers of this age have to acknowledge God, even if those who ruled at the time didn’t. This certainly added an extra layer of hope.
And that is the most important thing. Regardless of when it was written or who wrote it the main point is that we should all be faithful to God. That He will win in the end is one of the most important, timeless lessons that anyone can learn.
Erik Ritland is a journalist and musician from St. Paul, Minnesota. Ramblin’ On catalogs his writings on culture, music (including his own projects), sports, religion, and many other topics. You can reach him via email here.