Japan National Rail and the Japan Rail Companies
Japan’s railways started out as a collection of privately-owned lines, some built by groups of former nobles (daimyo, and members of the Samurai class) who had money to invest after being compensated for their holdings following the Restoration of Imperial power in 1868. In 1906, immediately after the Russo-Japanese war, the bulk of the nation’s railways (4,525 km) were nationalized by the government (the government had previously been closely associated with the privately owned 1,300 km Nippon Railway, which included portions of the future JR East Tōhoku Main Line and Jōban Line). Some smaller railways that were not considered necessary to a national network or militarily strategic were left in private ownership.
Japanese Government Railways, 1906 - 1949
Initially just called Kokuyū Tetsudō, which means “state-owned railway”, the nationalized railways were eventually known by the English name Japanese Government Railway or Japanese Government Railways (there doesn’t appear to have been a name in Japanese for the collection of all of them, and they may have continued to have individual identities). Up through the end of the second world war, the nationalized railways were administered by a government ministry. In 1949, during the Occupation of Japan by Allied forces, the JGR was reorganized into the Japanese National Railway(s), or JNR.
After the railways were nationalized, electrification became increasingly popular both within and between cities, although a very small percentage of overall track-kilometers were electrified. In 1909, the Yamanote line around western Tōkyō was electrified. Electrical components were imported from companies in America, Germany and Great Britain. Domestic production began in 1916 during the first world war, but dependence on foreign companies continued until 1930. In 1927, JGR operated 12,864 km of track, while private railways (219 of them) operated 5,370 km of track.
Between 1909 and the beginning of the recession of 1920 repeated attempts were made to begin converting Japan’s narrow-gauge tracks to standard gauge, following similar activities in Europe and America. Estimates at the time were that this would have a beneficial effect on the country, and would cost little more than maintaining the existing track. But for a variety of reasons, some of them apparently military, these proposals never went beyond the planning stages.
Electrification, primarily in urban areas, increased after 1910 due to increasing costs for coal, as well as the faster speeds it brought. But electrified lines still made up a small percentage of overall track-kilometers until the post-war era.
Japanese National Railways, 1949 - 1987 (日本国有鉄道 Nippon Kokuyū Tetsudō)
The Japanese National Railway (or Railways), commonly abbreviated JNR, was a state-owned corporation formed to operate the national railways. This was nominally a public corporation, but for most of its existence it operated at a loss, and was heavily subsidized by the government, which effectively owned it. Part of the problem was the need to subsidize service of unprofitable branch lines (often the only good means of transportation from isolated areas to the outside world), and part of it after 1964 was the massive and continuing investment in the construction of the Shinkansen high-speed lines.
The Shinkansen, which used private rights-of-way with Standard Gauge (1,435 mm) track and high voltage alternating current electrification for high-speed passenger transport, was first introduced in 1964 between Tōkyō and Osaka, in time for the Tōkyō Olympics, and expanded rapidly. Additional lines serving other parts of the country were built during succeeding decades.
Starting in 1964 JNR lost money, lots of money, and operated under government subsidy. It wasn’t just the Shinkansen’s fault. Japan had the same issues as other countries: shifting of traffic to subsidized highways, loss of passengers to air and automobile, and the increasing cost of labor in a labor-intensive system, as well as government-mandated continuance of money-losing branch lines. Continued funding of massively-expensive Shinkansen construction was only the cherry on top.
By the 1980’s, losses were mounting and both public and government perception of JNR was turning negative. Attempts to correct its profitability failed, and it was eventually decided to privatize the company. In 1987, JNR was broken up into seven companies (six regional passenger operators, and JR Freight) under the collective name of the Japan Rail Group (written “JRグループ”, or “Jeiāru Gurūpu” or just “JR”).
These companies, including JR East which operates trains in the Tōkyō region and the eastern portion of the country, owned almost all of the track, with the one freight company (JR Freight), largely operating using trackage rights over lines controlled by the other six. In 1987, just before the breakup, JNR had 27,600 km of track.
Japan Rail (1987 - present)
After massive layoffs (over 20% of the more than a quarter-million workforce) and sales of non-productive assets, the privatization approach worked, and the JR Group companies became profitable. JR East became publicly traded in 1993, and the last remnants of government ownership were removed in 2002 (or 2004 according to Japanese wikipedia). The final step in the privatization of JNR was the sale of the government-held shares of JR Tōkai (aka., JR Central) in 2006, although JR Freight’s parent corporation remains government-owned.