The late nineteenth and early twentieth century were a brutal time for American wildlife, with many species pushed to the brink of extinction. (Some are endangered to this day.) And yet these decades also saw the dawn of the conservationist movement. Into this contradictory era came William Temple Hornaday, a larger-than-life dynamo who almost uncannily embodies these conflicting threads in our history. In The Most Defiant Devil, a compelling new biography of this complex figure, Gregory Dehler explores the life of Hornaday the hunter, museum builder, zoologist, author, conservationist, and anti-Bolshevist crusader. A deeply religious man, he was nonetheless anything but peaceful and was racist even by his era’s standards, going so far as to display an Mbuti pygmy as a 'living specimen' in a zoo. A passionate hunter, Hornaday killed thousands of animals, including some of the last wild buffalo in America, but he was far ahead of his time in his influential views on the protection of wildlife. Hornaday designed and built the New York Zoological Park (which became the Bronx Zoo) and was chief taxidermist for what would later become the Smithsonian Museum of Natural History. In this single, fascinating individual, we can discern some of the Progressive Era's most destructive forces and some of its most enlightened visions.