Grand Trunk Western began as a route for the Grand Trunk Railway (GTR) to link its line to Chicago through lower Michigan. GTR's objective was to have a mainline from shipping ports in Portland, Maine, to rail connections in Chicago through the southern part of the Province of Canada that would serve Toronto and Montreal.[3][4]
In 1859 the Grand Trunk completed its route to Sarnia, Canada West, and began a ferry service across the St. Clair River to Port Huron. GTR leased the Chicago, Detroit and Canada Grand Trunk Junction Railroad to reach Detroit and from there then ran over the Michigan Central Railroad's line from Detroit into Chicago.[4] It was on the line from Port Huron to Detroit that a 12-year-old Thomas Edison held his first job as a newsboy and candy butcher onboard passenger trains.[5] Grand Trunk established its own route to Chicago across Michigan when the New York Central Railroad's William Henry Vanderbilt took over control of the Michigan Central in 1878.[5] GTR sought to put together a route by acquiring three railroads it had already been sending some of its Chicago-bound trains on since 1877.[4] The Chicago and Lake Huron Railroad, the Chicago and Northeastern Railroad (C&NE) and the Peninsular Railway of Michigan and Indiana together formed a direct route from Port Huron through Flint and Lansing, Michigan, to Valparaiso, Indiana, where it connected into Chicago on the Pittsburgh, Fort Wayne & Chicago Railroad. However, Vanderbilt owned the Chicago and Northeastern section of the route from Flint to Lansing and charged Grand Trunk higher rates to move its freight over the line. Vanderbilt soon sold the C&NE to Grand Trunk when GTR bought the other two lines in 1879 and proposed building its own route between Flint and Lansing just north of Vanderbilt's line.[4] Grand Trunk completed its own route into Chicago from Valparaiso in 1880 and incorporated the entire line from Port Huron to Chicago as the Chicago and Grand Trunk Railway.[6]