The Olympian and its successor the Olympian Hiawatha were passenger trains operated by the Chicago, Milwaukee, St. Paul and Pacific Railroad (the "Milwaukee Road") between Chicago and the Pacific Northwest. The Olympian operated from 1911 to 1947 and was, along with its running mate the Columbian, the first all-steel train to operate in the Pacific Northwest. The streamlined Olympian Hiawatha operated from 1947 to 1961 and was one of several Milwaukee Road trains to carry the name "Hiawatha." The Olympian Hiawatha was designed by industrial designer Brooks Stevens and included the distinctive glassed-in "Skytop" observation-sleeping cars. It later featured full-length "Super Dome" cars.
In 1909 the Milwaukee Road opened the "Puget Sound extension" from South Dakota to Seattle and Tacoma, completing the last line from Chicago to the coast. The Milwaukee Road ordered cars for two new all-steel luxury trains to run Chicago-Milwaukee-St. Paul-Seattle-Tacoma. The two new trains debuted on May 28, 1911. They were the first all-steel trains to operate in the Pacific Northwest. The Milwaukee Road named the two trains the Olympian and Columbian. The Olympian took 72 hours between Chicago and Seattle, necessitating seven sets of equipment to cover the service. Starting in 1914 the Olympian used the route of the Union Pacific Railroad to serve Spokane, Washington.
In 1915 the Milwaukee completed its first electrified section of rail line, from Harlowton to Deer Lodge, Montana, a feat that was advertised to passengers since electrification eliminated the soot normally associated with steam-powered rail travel prior to the era of air-conditioning. Extensions in the 1910s and 1920s resulted in 649 miles (1,044 km) of electrified main line, in Montana/Idaho and over the Cascades in Washington. The 440 miles (710 km) of electrified line between Harlowton, Montana and Avery, Idaho was the longest continuous electrified rail line in the world.