The federal government had encouraged the Grand Trunk Railway (GTR) system in the 1870s to consider building the transcontinental rail line.

When Grand Trunk balked at building a railway using the survey, the government turned to the privately owned Canadian Pacific.

The Canadian Northern Railway (CNoR) was an upstart regional system for the prairies that had begun in Manitoba under entrepreneurs William Mackenzie and Donald Mann in 1899 through their amalgamation of several smaller branch lines.

In keeping with the trend of railways to exploit virgin territories, the government-backed "transcon" would run from the port of Prince Rupert, British Columbia, across the northern portion of the prairies to Winnipeg, and from there across northern Ontario and Quebec to Quebec City where it would cross the St. Lawrence River and continue on to its eastern terminus at Moncton, New Brunswick, by way of a route directly across central New Brunswick.

The territory across northern Quebec and Ontario to Winnipeg, through the heart of the Canadian Shield, posed an extremely difficult construction obstacle.

The NTR in those provinces never lived up to its expectations for creating traffic, but for a time, it aided the resource-rich mining communities of northern Ontario and northwestern Quebec.

Under CNR (CN post-1960), the NTR route across northern Quebec and Ontario became a marginal secondary main line, with little in the way of through freight or passenger traffic.

At Nakina, the CNR had constructed the Longlac-Nakina Cut-Off, a 29.4-mile (47.3 km) section of track linking the NTR with the Canadian Northern line at Longlac, which was completed in 1924.

West of Nakina, the combined NTR/GTPR line forms CN's transcontinental mainline through to Tête Jaune Cache, British Columbia, and sees very heavy traffic.

In the 1990s and 2000s, congestion at many ports along the west coast of North America made the GTPR's development of Prince Rupert an attractive alternative.