As comfortable in bear-skin pants under the northern lights as in a tuxedo at the theatre in Copenhagen, Knud Rasmussen undertook some of the most astounding feats of endurance in the annals of polar exploration. He travelled without the elaborate preparations and large teams employed by other explorers, surviving with only a few Inuit assistants and by living off the land. His crowning achievement, made famous as the Fifth Thule Expedition, was a three-year, 20,000 mile odyssey by dog sled from Greenland to Alaska to reveal the common origins of all circumpolar peoples.