Challenge of the Yukon was a long-running radio series that began on Detroit’s station WXYZ (as had The Lone Ranger and The Green Hornet), and an example of a Northern genre story. The series was first heard on February 3, 1938.

The program was an adventure series about Sergeant William Preston of the Northwest Mounted Police and his lead sled dog, Yukon King, as they fought evildoers in the Northern wilderness during the Gold Rush of the 1890s. Preston, according to radio historian Jim Harmon, first joined the Mounties to capture his father’s killer, and when he was successful, he was promoted to Sergeant. Preston worked under the command of Inspector Conrad, and in the early years was often assisted by a French-Canadian guide named Pierre.

Preston’s staunchest ally, who was arguably the true star of the show and indeed often did more work than he did, was the brave Alaskan husky, Yukon King. Typical plots involved the pair helping injured trappers, tracking down smugglers, or saving cabin dwellers from wolverines. Sgt. Preston’s faithful steed was Rex, used primarily in the summer months, but generally Yukon King and his dog team were the key mode of transportation (as signaled by Preston’s cry of “On, King! On, you huskies!”

There is some confusion regarding King’s actual breed. The producers seemed to use malamute and husky interchangeably. At least once, Preston answered “malamute” to the question from another character. In the early radio shows, the cry of “On, you huskies!” would alternate with “On, you malamutes” from show to show.

Von Reznicek’s Donna Diana Overture was the pulsing theme music, and the episodes ended with the official pronouncement, well, King, this case is closed.

Following the success of The Lone Ranger and The Green Hornet, George W. Trendle, the station owner, asked for a similar adventure show, but with a dog as the hero. According to WXYZ staffer Dick Osgood, in his history of the station, Trendle insisted that it not be “a dog like Lassie because.. this must be an action story. It had to be a working dog.” Writer Tom Dougall, who had been influenced by the poems of Robert W. Service, naturally chose a Husky. The dog was originally called Mogo, but after criticism by Trendle, Dougall re-christened the canine King. Dougall likewise created Sgt. Preston and the French-Canadian guide. Fran Striker, who wrote for The Lone Ranger, also contributed scripts.

However, Trendle’s criticism of Dougall may have had another reason behind it. Shortly before the two Trendle series aired (The Lone Ranger and Challenge of the Yukon), popular author Zane Grey had a book in circulation (Lone Star Ranger) about a Texas Ranger like The Lone Ranger and a comic book series in circulation (King of the Royal Mounted) about the adventures of Sgt. King, a Royal Canadian Mounted Policeman like Sgt. Preston. It could be that Trendle borrowed both ideas from Grey’s work and wanted to retain the name “King” as a tribute to Grey, who died after a lengthy illness one year following the first airing of Challenge of the Yukon.

Challenge of the Yukon began as a 15-minute serial, airing locally from 1938 until May 28, 1947. Shortly thereafter, the program acquired a sponsor, Quaker Oats, and the series, in a half-hour format, moved to the networks. The program aired on ABC from June 12, 1947, to December 30, 1949. It was then heard on The Mutual Broadcasting System from January 2, 1950, through the final broadcast on June 9, 1955. The title changed from Challenge of the Yukon to Sergeant Preston of the Yukon in November 1951 and remained under that name through the end of the series and into television.