As adventurers from around the world raced to reach the South Pole and achieve other polar firsts in the early 1900s, outsider Ernest Shackleton and his motley expeditions would outshine even the British navy, becoming icons of the Heroic Age of Antarctic Exploration. Known for prizing loyalty, leadership, and skill without regard for rank or social class""and for bringing men back alive""Shackleton completed three death-defying Antarctic...