Tried by War: Abraham Lincoln as Commander in Chief by James M. McPherson.
McPherson, retired professor from Princeton and the leading writer of his generation on the War of the Rebellion, describes the political, strategic and personnel issues Lincoln faced managing the War. It’s a well-paced narrative focusing on the Commander in Chief, not the armies.
Hello, Everybody!: The Dawn of American Radio by Anthony Rudel.
Rudel has written a topical history of early radio — commercial development, sports, news, religion, entertainment. Informative and interesting, but I’m nearly half way in and have set it aside as a little too inclusive and with insufficient storytelling. Good enough that I expect to get back to it when I finish McPherson, though.
If you’re interested in some fiction when you finish, pick up a copy of Neal Stephenson’s Anathem. It’s a monster, but a great story that will get your gears moving.