Seppala and his beloved Togo

Seppala and Kaasen were the two most celebrated mushers in the Serum Run, Seppala because he ran the most dangerous part of the race and Kaasen because he ran the last leg of the race. 

Leonard Seppala was a famous sled dog racer by 1922, the year that Balto was born. Sepp, as his friends called him, had won every big race in Alaska, including the 408-mile All-Alaska Sweepstakes 3 years in a row.  Sepp's No. 1 leader in 1925 was Togo, a nine-year-old male Siberian Husky. Togo was a born genius and champion veteran racer. Balto was another one of Seppala's dogs. He was one of the lesser huskies, in Sepp's opinion. 

Kaasen and Balto

Gunnar Kaasen was Seppala's dog handler. Seppala and Kaasen worked for a gold mining company, driving dog teams with supplies to the outlying gold camps. Unlike Sepp,  Kaasen favored Balto.

Being the most experienced and respected musher at that time Seppala was asked to run the most dangerous part of the relay.  Gunnar Kaasen joined the race as an addendum when Governor Bone tried to speed things up by adding mushers.Without Seppala's knowledge (since he was already on the trail) Kaasen used Seppala's remaining dogs, and picked Balto as the leader even though he knew that this would anger
Seppala!  Balto rose to the occasion.