I didn’t want to write a biography of Barth. That would take many years, deep funding,  and fluency in German, all unobtainable. Besides, what really interested me was his great journey and the British response to it. I wanted to tell an exciting story with a compelling main character. Specifically, I wanted to take readers on an expedition into Islamic Africa with a perceptive traveler—Barth—through decaying empires and young nations, on grim desert marches and slave raids, into cultures sometimes surprising for their savagery, sometimes for their sophistication. It would be an historical adventure.

Return of the Sultan of Massenya, from Travels and Discoveries

Historical journalism was new for me, but my guiding principles wouldn’t change. No straying from the known facts. No fabricated scenes or dialogue. No unsubstantiated speculation about the invisible crevices of Barth’s mind. Obvious principles, perhaps, but often flouted these days by “imaginative re-creations” of someone’s life and by histories “based on a true story,” a euphemism for “fiction.”

I also decided to avoid the intrusion of contemporary voices. No quotations from modern scholars, no commentary by present-day Europeans and Africans, no first-person distractions (“Look at me in Barth’s footsteps”). I didn’t want to slow down the story or break the reader’s immersion in nineteenth-century African travel. (After I finished the book, I found a wonderful example of what I hoped to do: Candace Millard’s The River of Doubt: Theodore Roosevelt’s Darkest Journey.)

Some of this would have made Barth nod. His brother-in-law and biographer, Gustav von Schubert, described Barth’s devotion to truth and knowledge as priest-like. A scientist to his very soul, Barth deplored sloppiness and inaccuracy. He was sure he could measure everything precisely, from the water temperature in a desert well to a man’s integrity. It never entered his mind to fudge his data or his opinions—an impolitic trait that would cost him. Unlike many of his fellow explorers, he avoided self-display, and after his return he was puzzled when the public preferred travel accounts that were more entertaining than scientific, such as David Livingstone’s. (The two men knew and admired each other.)

In his personal life Barth could be as touchy as an anemone—nothing riled him more than assaults on his integrity—but as a scientist he was completely trustworthy. His few errors don’t stem from laziness or malice.

As a journalist, I was astonished by his skills as an observer, interviewer, and investigator, even under conditions that were physically or psychologically debilitating. Whether reeling with sickness or threatened with death, he still sought out informants and took detailed notes about everything around him. A typical example: near Timbuktu, 200 armed men crowded into his room and eyed his luggage, piled behind him. While waiting for their next move, Barth took out his notebook and wrote a thorough description of their clothing and weapons. Cool Hand Heinrich.