The "Big Four" was a name used to describe the four largest railway companies in the United Kingdom in the period 1923–1947. The name was coined by The Railway Magazine in its issue of February 1923: "The Big Four of the New Railway Era".
The Big Four were:
Great Western Railway (GWR) London, Midland and Scottish Railway (LMS) London and North Eastern Railway (LNER) Southern Railway (SR)
The companies were formed as a result of the Railways Act 1921, in a process known as "The Grouping" (of the railways), which came into effect on 1 January 1923.
On 1 January 1948, the companies were nationalised to form British Railways as a result of the Transport Act 1947.
Characterisation
The three larger companies relied heavily on freight (especially coal), as well as long-distance passenger traffic. The Southern Railway, in contrast, was predominantly a passenger railway, which, despite its small size, carried more than a quarter of the total UK passenger traffic. That was because the area it served included some of the most densely-populated parts of the country and many of the well-patronised commuter lines radiating from London. It responded to that geography by pursuing a vigorous policy of electrification.
The GWR was the only company to retain its pre-grouping identity, which it duly imposed on all the companies it absorbed. However, the other three found that former influences remained strong. The Southern's management remained decentralised, respecting the three distinct bundles of routes inherited from its constituents. The LMS struggled to reconcile different traditions, especially in locomotive engineering, only resolving that situation in 1932 with the appointment of Sir William Stanier, from the GWR, as chief mechanical engineer. The LNER never made a profit, a fact partly accounted for by having inherited the huge debts incurred by the Great Central Railway in building its extension to London.
Joint activities
Although nominally in competition, the four companies worked together on projects of significance to the railway industry as a whole.
During World War II, the railway companies' managements were united, effectively becoming one company, under the direction of the Railway Executive Committee. The railways were hired by the Government from 1 January 1941, to continue for one year after the end of the war. In return, a fixed Annual Rent of £43,468,705 was payable, divided between the companies according to a set formula.
A commission was set up under the chairmanship of Sir Ernest Lemon to consider the post-war planning and reconstruction of the railways, with representatives of the Big Four and the London Passenger Transport Board.
Joint lines
Each company operated a number of lines jointly with one or more of the others, a situation which arose when the former joint owners of a route were placed into different post-grouping companies. Most of these were situated at or near the boundaries between two or more of the companies; however there were some notable examples which extended beyond this hinterland zone.
The number of jointly operated lines was greatly reduced by the grouping but a substantial number survived, including the Cheshire Lines Committee, the Forth Bridge Railway Company, the Midland and Great Northern Joint Railway (all LMS/LNER) and the Somerset and Dorset Joint Railway (LMS/SR). At in excess of 180 track miles, the M&GN was the largest jointly operated network in Great Britain, and extended from Peterborough to the East Anglian coast. It was wholly incorporated into the LNER in 1936. The S&D connected Bath and Bournemouth, and wound its way through territory otherwise dominated by the GWR. The LMS was responsible for its locomotives and the Southern for the infrastructure. Initially, the S&D had its own locomotives but these were absorbed into LMS stock in 1930. Further simplification of the railway map, long advocated, was not achieved until nationalisation. One joint operation, the Fishguard & Rosslare Railways & Harbours Company, which Irish independence had rendered international, survives to this day.