Marrin is a great historian-- he picks out the most interesting quotations and tidbits from primary sources to give readers a true taste of the Civil War, and he "show, don't tell"s to the max.
With that said, I found many of the battle descriptions and narrative about the movements of the Union and Confederate armies dry-- this book could have used a discerning editor.
Five stars on the biographical details and on descriptions of Ulysses and Julia, Abraham and Mary Todd, and other important men and women of the time. Five stars for allowing children to engage with the complexity of the history and of our heroes. Five stars for not editing out the tough stuff but forcing people to face the cruelty of the past. (Including photos of the dead and plenty of quotations in which the casual racism of the time is on full display in all of its abhorrence.)
But I docked a star because some of the book just will put you right to sleep unless you're a true Civil War buff, and probably won't appeal to the impatient contemporary reader as it comes off too much like textbook, not narrative, history.