Abraham Lincoln, by Carl Sandburg.
This is an old classic on the life of Lincoln. It is a tome. I had heard about this book (originally a multi-volume set) but never read it. Now I am listening to it on Audible and have 15 hours left of the 42 hours of narration. Sandburg includes massive amounts of detail from the lives of secondary characters. He often detours to discuss topics like the life history of a sea-captain or the history of a newspaper in Chicago. Listening or reading can be tedious, but it does have the effect of immersing one’s mind into the world of Lincoln and therefore into the world of an extremely important part of America’s history.
There is no direct spiritual content for the Christian in this book. I think well-rounded Christians should be aware of history and consciously observe God’s moving among nations. However, this is probably not the best book on the Civil War, or Lincoln, for someone who is not an avid reader of history. I would suggest “Team of Rivals”, by Doris Kearns Goodwin.