Portions of the Iditarod Trail were used by the Native Alaskan Inupiaq and Athabaskan peoples hundreds of years before the arrival of Russian fur traders in the 1800s,[1] but the trail reached its peak between the late 1880s and the mid-1920s as miners arrived to dig coal and later gold, especially after the Alaska gold rushes at Nome in 1898,[1][2] and at the "Inland Empire" along the Kuskokwim Mountains between the Yukon and Kuskokwim rivers, in 1908. The primary communication and transportation link to the rest of the world during the summer was the steamship, but between October and June the northern ports like Nome became icebound, and dog sleds delivered mail, firewood, mining equipment, gold ore, food, furs, and other needed supplies between the trading posts and settlements across the Interior and along the western coast. Roadhouses where travellers could spend the night sprang up every 14 to 30 miles (23 to 48 km) until the end of the 1920s, when the mail carriers were replaced by bush pilots flying small aircraft, and the roadhouses vanished. Dog sledding persisted in the rural parts of Alaska, but was almost driven into extinction by the increased use of snowmobiles in the 1960s.

During its heyday, mushing was also a popular sport during the winter, when mining towns shut down. The first major competition was the tremendously popular 1908 All-Alaska Sweepstakes (AAS), which was started by Allan "Scotty" Alexander Allan, and ran 408 miles (657 km) from Nome to Candle and back.[3] In 1910, this event introduced the first Siberian Huskies to Alaska, where they quickly became the favored racing dog, replacing the Alaskan Malamute and mongrels bred from imported huskies.

The original Iditarod start had nothing to do with the serum run or the famous dog, Balto.

Joe Redington Sr. had the original idea to race a portion of the Iditarod trail. Joe Redington Sr. (named the "Father of the Iditarod" by one of the local newspapers) asked his friends, Gleo Huyck and Tom Johnson (school teachers and dog mushers) to join him in creating this new endeavor. The original plan was to race from Knik to Iditarod and back. Their friend, Bill Weimar, had the idea to start the race in Anchorage because it had a larger population at both ends of the race. They cleared a portion of the trail. The first race, known as the Iditarod Trail Race (The Last Great Race), was held in 1973.

Redington along with two school teachers, Gleo Huyck and Tom Johnson, made the Iditarod Race possible. The three co-founders of the race started in October 1972 to plan the now famous race. A major fundraising campaign which raised a purse of $51,000 was also started at the same time. This race was the first true Iditarod Race and was held in 1973, attracting a field of 34 mushers, 22 of whom completed the race.

Dorothy Page had nothing to do with the 1973 race, stating that she "washes her hands of the event".

The event was a success; even though the purse dropped in the 1974 race, the popularity caused the field of mushers to rise to 44, and corporate sponsorship in 1975 put the race on secure financial footing. Despite the loss of sponsors during a dog-abuse scandal in 1976, the Iditarod caused a resurgence of recreational mushing in the 1970s, and has continued to grow until it is now the largest sporting event in the state. The race was originally patterned after the All Alaska Sweepstakes races held early in the 20th century.

The main route of the Iditarod trail extends 938 miles (1,510 km) from Seward in the south to Nome in the northwest, and was first surveyed by Walter Goodwin in 1908, and then cleared and marked by the Alaska Road Commission in 1911 and 1912. The entire network of branching paths covers a total of 2,450 miles (3,940 km). Except for the start in Anchorage, the modern race follows parts of the historic Iditarod trail.