Leonhard Seppala was a Norwegian-American dog musher known for his remarkable role in the 1925 serum run to Nome, Alaska. He led a team of sled dogs, including his famous lead dog, Togo, over treacherous terrain to deliver diphtheria antitoxin to combat an outbreak in the remote town. Seppala was born on March 14, 1877, in Norway and later moved to Alaska, where he became a prominent figure in the sport of dog mushing. His skills and dedication earned him recognition, and he is often celebrated for his contributions to the history of sled dog racing.