The Milwaukee Road enjoyed temporary success after World War II. Out of bankruptcy and with the wartime ban on new passenger service lifted, the company upgraded its trains. The Olympian Hiawatha began running between Chicago and the Puget Sound over the Pacific Extension in 1947, and the Twin Cities Hiawatha received new equipment in 1948. Dieselisation accelerated and was complete by 1956. In 1955, the Milwaukee Road took over from the Chicago and North Western's handing of Union Pacific's Overland Route streamliners between Chicago and Omaha. The whole railroad industry found itself in decline in the late 1950s and the 1960s, but the Milwaukee Road was hit particularly hard. The Midwest was overbuilt with a plethora of competing railroads, while the competition on the transcontinental routes to the Pacific was tough. The premier transcontinental streamliner, the Olympian Hiawatha, despite innovative scenic observation cars, was mothballed in 1961, becoming the first visible casualty. The resignation of President John P. Kiley in 1957 and his replacement with the fairly inexperienced William John Quinn was a pivotal moment. From that point onward, the road's management was fixated on merger with another railroad as the solution to the Milwaukee's problems. Railroad mergers had to be approved by the Interstate Commerce Commission, and in 1969 the ICC effectively blocked the merger with the Chicago and North Western Railway (C&NW) that the Milwaukee Road had counted on and had been planning for since 1964. The ICC asked for terms that the C&NW was not willing to agree to. The merger of the "Hill Lines" was approved at around the same time, and the merged Burlington Northern came into being.
