In River of the Gods, Candice Millard presents an historical narrative that looks at a famous set of explorations through a new lens, that of character. The story of the search for the source of the Nile has been told before, many times in fact, but Millard’s purpose is not to recount the scientific or geographical facts as others have. Rather, she focuses on the people of the expeditions, both the commanders and the men in the ranks.

Millard paints detailed portraits of Richard Burton and John Hanning Speke, presenting their good qualities but not hesitating to critique their failings. Burton’s character, for instance, shows both his courage and depression, his leadership and his scandal. Speke ends up coming across as much more negative overall because of his tendency to hold tightly to and act on grudges, but the author also describes his courage and discipline. Millard sets both of these men in the context of their age as well, explaining their ideas in terms of the era but also pointing out flawed thinking, especially in terms of racism and Speke’s attachment to the Hamitic myth.

Millard allows her characters to speak for themselves by incorporating a wide assortment of primary sources. She quotes Burton’s published works and personal letters and papers so that the man himself has a voice. His character appears in high relief, for instance, through quotations like “Of the gladdest moments in human life, methinks, is the departure upon a distant journey into unknown lands. Shaking off with one mighty effort the fetters of Habit, the leaden weight of Routine.” The author also allows Burton to express his views about Speke. When Speke in his delirium raves against Burton, Burton is stunned. “I never should have known that he was pondering these things in his heart,” Burton writes, taken aback by his companion’s bitterness.

The author allows Speke his own voice, too, and it appears as a sharp contrast to that of Burton. Speke’s comments are often petty, angry, and self-centered. Before setting out for his side journey to Nyanza, for instance, he grumbles about his boredom. “There is literally nothing to write about in this uninteresting country nothing could surpass these tracks, jungles, plains etc. for dull sameness.” Where Burton saw unending interest, Speke descended into complaints when he did not get his way. Millard’s use of their words emphasizes their differences.

Millard enhances her presentation of Burton and Speke by allowing others to speak about them directly and offer outside perspectives. Isabel Burton’s voice appears frequently to characterize her husband, pointing out aspects of his personality that others might not have recognized. Readers might question the validity of Isabel’s observations and wonder if she was seeing her husband clearly or through the lens of her own presuppositions, yet her words provide a broader, more nuanced portrait, as, for instance, when she asserts, “He is not at all the man . . . that people take him to be, or that he sometimes, for fun, pretends to be.” The same can be said of firsthand descriptions of Speke from Burton, Grant, and Murchison. Speke’s character is rounded out by their comments, as when Burton noted the “noble qualities of energy, courage, and perseverance” that Speke showed.

Millard’s account of the expeditions in search of the Nile’s source also stands apart from other such histories because of her emphasis on the contributions of men like Sidi Mubarak Bombay. Millard argues that the contributions of native Africans to expeditions like those of Burton and Speke have long been ignored, and she attempts to correct this. Without...