In 1919, the Intercolonial Canadian Northern, National Transcontinental and Grand Trunk Pacific became part of a government railway system known as the Canadian National Railways (CN). The railway was referred to as the Canadian National Railways (CNR) between 1918 and 1960 and as Canadian National (CN) from 1960 to the present day. In January 1923, the Grand Trunk Railway officially became part of the railway. In 1937, CN organised formation of Trans-Canada Airlines (now Air Canada) and in 1938 the federal government cancelled more than $1 billion of its inherited debt. As a result, CN was able to purchase a large number of Canadian-built steam locomotives which were finished and serviced in the corporation’s own huge shops at Pointe St-Charles, Montréal. These locomotives hauled millions of tons of freight and thousands of troops during the Second World War.

In the 1950s and 1960s, CN was modernized by reorganisation of its 80 subsidiaries into 30 companies, also with conversion to diesel locomotives and electronic signalling and the head office moved to Montréal in Quebec. In the late 1970s, CN started to divest itself of non-rail businesses, including real estate, hotels, and CNCP Telecommunications. Around the same time, Air Canada and VIA Rail, CN’s passenger train subsidiary became separate Crown corporations.

On November 17th 1995, the Canadian Federal Government privatized the Canadian National Railway. According to the CN Commercialization Act of 1995, the company headquarters had to remain in Montréal, which ensured that CN would remain a Canadian corporation. Over the next decade, the company expanded significantly into the United States, it purchased US rail company Illinois Central Corp for $2.4 billion. It later acquired Wisconsin Central (2001), the rail and marine holdings of Great Lakes Transportation (2004), shares of BC Rail (2004), and the Elgin, Joliet & Eastern Railway (2009).

In the present day CN is the largest railway in Canada, in terms of both revenue and the physical size of its rail network, and is currently Canada’s only transcontinental railway company, spanning Canada from the Atlantic Coast in Nova Scotia to the Pacific Coast in British Columbia. It is the longest railway system in North America controlling more than 30,000km of track in Canada and the United States.