In the last three decades of the 19th century, the U.S. Army considered the eradication of the buffalo essential to victory in its ongoing war on Native Americans. A scientist and a journalist, George Bird Grinnell would lead the battle to save the buffalo from extinction. Fighting in the pages of magazines, in Washington's halls of power, and in the frozen valleys of Yellowstone, Grinnell and his allies sought to preserve an icon. In this history by the author of the novel The Revenant Grinnell crosses paths with some fo the most remarkable characters of the American West: John James Audubon, Buffalo Bill, George Armstrong Custer, and Theodore Roosevelt.