What is the author's tone in Lincoln by David Herbert Donald?

Donald's tone is detached and objective throughout the biography. He treats the subjects of his history with respect and avoids making extreme judgments even when it is apparent that the contemporaries he describes had very strong opinions of one another. While Donald is respectful in his tone toward Lincoln, he is not reverential. Lincoln is a figure around whom many myths and legends have been created, however Donald treats him as a real person with ambitions, strengths and faults just as any other person.