What is the author's style in Bearing the Cross by David Garrow?

David Garrow wrote this book in order to chronicle Martin Luther King Jr.'s actions within the civil rights movement. Garrow appears to have intended to educate his reader about the civil rights movement, but also about the man behind many of the actions associated with the movement. The civil rights movement was a many faceted action that included demonstrations and violence instigated by many different organizations and leaders, some famous, some not.