The Chicago and North Western (reporting mark CNW) was a Class I railroad in the Midwestern United States.

The majority of the abandoned and sold lines were lightly trafficked branches in Iowa, Illinois, Minnesota, South Dakota and Wisconsin.

In 1911 a new freight yard and shops were built 13 miles west of Chicago in Proviso Township, which featured a mammoth, 58-stall roundhouse (a twin of the one in Fulton, Illinois).

[4] Changing traffic patterns and competition with automobiles and trucking disrupted the railroad's profitability by mid-20th century.

This road, like other lines depending strongly on transportation of crops, was adversely affected by government agricultural credit policies, which sealed a lot of products on the farms where they were produced.

A connection from Hayfield, Minnesota, to Clarion, Iowa, provided a Twin Cities to Omaha main line.

After the Chicago, Rock Island and Pacific Railroad (Rock Island) ceased operating on March 31, 1980, the North Western won a bidding war with the Soo Line Railroad to purchase the roughly 400-mile (640 km) "Spine Line" between the Twin Cities and Kansas City, Missouri, via Des Moines, Iowa.

The Interstate Commerce Commission (ICC) approved North Western's bid of $93 million on June 20, 1983.

The line was well-engineered, but because of deferred maintenance on the part of the bankrupt Rock Island, it required a major rehabilitation in 1984.

The company then began to abandon the Oelwein to Kansas City section of its former Chicago Great Western trackage, which duplicated Spine Line service.

[8] Ten miles of their line between North Freedom, Baraboo, and Devil's Lake were also flooded, and it isolated the C&NW's quarry supply in Rock Springs (a vintage diesel switcher from the nearby Mid-Continent Railway Museum assisted the Rock Springs quarry, until the flood cleared).

[11] By the time the flood ended, most of the C&NW's rail lines remained intact and were quickly reopened.

[15] A joint UP-CNW subsidiary, Western Railroad Properties, Inc., was also merged into the Union Pacific system in the acquisition.

Chicago and North Western locomotives continued to operate in their own paint schemes for several years after the acquisition (although some of them were gradually repainted into UP colors.)

Many former CNW units have received "patches" with a new road number and reporting mark to match their new owner's roster.

Union Pacific continues to follow its new tradition of releasing "Heritage" EMD SD70ACe units to represent the paint schemes of companies absorbed by UP.

Paul, was introduced in 1935 to compete with the Chicago, Burlington and Quincy's Zephyrs and the Milwaukee Road's Hiawathas.

CNW was the first system to start a high-speed Chicago-Twin Cities schedule because it used refurbished rather than new equipment, but in 1939, modernized the 400 with new E3A diesel locomotive pairs and streamlined cars.

These services lasted from 1889 to 1955, after which the CNW route to Chicago was changed to the Milwaukee Road's due to poor track conditions.

In 1974, responsibility for the commuter lines and equipment ownership transferred to the newly formed Regional Transportation Authority, whose rail division was later branded in 1984 as Metra.

The C&NW continued to run the lines under a "purchase of service" contract, in which the railroad maintained the right-of-way and operated trains on behalf of Metra.

Rails and ties north of the Cargill plant in Ringwood were removed during the 1980s, and the right of way converted to a trail.

[20][22] The steam tour took place in May 1982, dubbed the "Prosperity Special", to promote the C&NW's locomotive and rolling stock upgrades.

[20][23][24] As a result of the Prosperity Special’s success, additional steam tours took place in the ensuing years throughout Wisconsin, Minnesota, Iowa, and Illinois.

[23][25][26] Some of the trains used C&NW track rights to travel over Milwaukee Road and Burlington Northern trackage.

When originally built as single-line trackage, the C&NW arbitrarily placed its stations on the left-hand side of the tracks (when headed inbound toward Chicago).

Potatoes came to the yard from every point in the United States to be bought or traded by produce dealers and brokers.

The former Illinois Central line, now the Badger State Trail, runs on a bridge directly above the roundabout and has ramps connecting to the Capital City and Cannonball Paths.

It is a segment of a former St. Louis, Peoria and North Western Railway 38-mile (61.2 km) right-of-way (which was later folded into the CNW) that has been set aside for rail trail use.

Some of the older locomotives have been donated to parks and museums for preservation, and a few continue to operate on scenic or tourist railroads.