He [Carl Sandburg] worked for ten years on the Lincoln book. I know that at the end there was a kind of desperation that something might come between himself and getting it done. You can understand if you knew the labor of it. For example, Lincoln was assassinated on a Friday night and he read 300 American sermons delivered the following Sunday—just to search into how the country felt. So you can see behind each sentence in that Lincoln book there was search, search, testing for accuracy and truth into the past then distilling all that chaotic ocean into clear, musical, noble sentences.
Another letter says: “I have reached 2 o’clock in afternoon of Lincoln’s last day…”
—Brenda Ueland, “Carl Sandburg,” Strength To Your Sword Arm: Selected Writings (Holy Cow! Press, 1993)