The London and North Eastern Railway (LNER) was one of the four railway companies that were formed in 1923 due to the amalgamation of 1921. During the First World War the government had taken control of the railways for the purpose of the war effort. After the war ended it was decided that the railway companies could not competitively return to their prior state, and so the decision was made to combine the 120 existing railway companies into four companies, which became known as ‘the big four’. Smaller railway companies were merged together to form LNER, these previous companies consisted of; Great Central Railway, Great Eastern Railway, Great Northern Railway, Great North of Scotland Railway, Hull and Barnsley Railway, North British Railway and the North Eastern Railway. LNER was the second largest company of the ‘Big Four’ in terms of route miles (total route mileage amounted to 6700) and became famous for its prestigious high speed trains, including the Flying Scotsman and the Mallard, which reached speeds of 126mph (breaking the world record for steam). William Whitelaw, who was a public figure in Scotland, was appointed the first chairman of LNER operating mainly from the London headquarters. The management of LNER was decentralised as much as possible and one of Whitelaw’s main responsibilities became scrutinising proposals of expenditure, due to the shortage of investments. It was decided that the head of management should be Sir Lewis Wedgewood and it was under his management that three main headquarters should be created to best oversee the company. These areas were; Southern, North-Eastern, with offices being situated in York, and Scotland, which was then divided into Northern and Southern Scotland. By 1928 organisation in LNER had stabilised with the chairman being based in Marylebone, Chief General Manager being based in Kings Cross and the Southern headquarters being based in Liverpool. Sir Nigel Gresley became the first Chief Mechanical Engineer of the company. Each of the big four had a Chief Mechanical and Electrical Engineering department which was formed in 1923 with the creation of each company and after nationalisation in 1948, one CM&EE department was created. Gresley became very influential in the company, not only due to his designs of the Flying Scotsman and the Mallard, but also his Pacific designs and long-distance locomotives with the ability to overcome difficult operating conditions. Gresley died in office in 1941 and was succeeded by Edward Thompson, who remained CME until 1946. Arthur Peppercorn, a student of Gresley’s, succeeded Thompson but remained CME for just 18 months, as nationalisation cut short his career. After the Second World War all four railway companies were in financial trouble. The growth of road transport and the effects of the war had meant that each company was in need of severe maintenance work (LMS calculated it would have to spend £40 million on maintenance). Investors of the railways were also at a loss, the LNER’s investors had received no dividend since 1941. With the arrival of a new labour government in 1945, the decision to nationalise all public transport was put forward and in 1948 the ‘Big Four’ were replaced with the British Transport Commission, which separated LNER into Eastern and North Eastern Regions, as well as surrendering the Scottish territory.

Railways in Britain were nationalised under the terms of the Transport Act 1947 which came into effect on 1 January 1948. The Railway Executive, a corporate body subordinate to the British Transport Commission, was created to manage and operate the railways. It divided them into six geographical regions, largely based on the areas served by the pre-nationalisation railway companies. Between 1948 and 1952 the regional manager of the North Eastern Region was responsible to the Railway Executive for day to day operations in his region. After the Railway Executive was abolished in 1952, he reported to the British Transport Commission (BTC). In 1963, BTC itself was abolished and replaced by British Railways Board (BRB). Between 1963 and 1968 was a statutory board in accordance with the provisions of the Transport Act 1962, subordinate to and reporting to BRB. The North Eastern Region was a near direct post-nationalisation descendant the London North Eastern Railway (LNER) and covered a similar geographic area . The former LNER lines in England were subdivided into the Eastern Region and the North Eastern Region. The North Eastern Region covered everything east of the Pennines from the Humber to the Scottish border including the northern section of the east coast main line (York, Newcastle and Berwick). The main lines included the northern LNER lines in England and all ex-LMS lines east of Skipton. With both Hull and the Tyne ports and the industrial areas of Yorkshire, Durham and Northumberland this region handled a considerable quantity of heavy freight. In 1958 in a major re-drawing of the region boundaries The North Eastern Region gained former London Midland Scottish (LMS) lines that lay in the present-day West and North Yorkshire. The North Eastern Region was disbanded and merged with the Eastern Region in 1967 and the region's headquarters in York became the new headquarters.

Railways in Britain were nationalised under the terms of the Transport Act 1947 which came into effect on 1 January 1948. The Railway Executive, a corporate body subordinate to the British Transport Commission, was created to manage and operate the railways. It divided them into six geographical regions, largely based on the areas served by the pre-nationalisation railway companies. Between 1948 and 1952 the regional manager of the Eastern Region was responsible to the Railway Executive for day to day operations in his region. After the Railway Executive was abolished in 1952, he reported to the British Transport Commission (BTC). In 1963, BTC itself was abolished and replaced by British Railways Board (BRB). Between 1963 and 1968 the Eastern Region was a statutory board in accordance with the provisions of the Transport Act 1962, subordinate to and reporting to BRB. In 1957 the Eastern Region was divided into three lines – Great Eastern, Great Northern and London, Tilbury, and Southend (transferred in to the Eastern Region in 1949) each under a Line Traffic Manager. The lines were managed as the Great Northern (Kings Cross services) and the Great Eastern (Liverpool Street and Fenchurch Street services), with the regional headquarters at 55 Liverpool Street. The Chief Regional Officer in 1948 was Charles K. Bird. The Eastern region lines connected Liverpool Street in the City of London with destinations in east London and the east of England. The Northern lines include London King's Cross railway station to Stevenage in Hertfordshire and Peterborough in Cambridgeshire. Commuter services via the North London Line were also run into Broad Street station, but these were slowly run down and diverted to other destinations, with the station eventually being closed in 1986. In 1967 the North Eastern Region was absorbed into the Eastern Region and the region's headquarters in York became the new headquarters . By 1988 the Eastern Region had been divided again into the Eastern Region and the new Anglia Region, with the boundary points being between Peterborough and Whittlesea, and between Royston and Meldreth. The Eastern Region continued the London North Eastern Railway’s electrification programme as part of the 1955 Modernisation Plan. However, the British Transport Commission felt that many Eastern Region routes would not benefit from this; indeed, many of the rural lines proposed for electrification were in fact closed entirely by Dr Beeching. Instead, the Eastern Region had to content itself with being an early adopter of diesel-electric power, replacing steam at the earliest opportunity The region ceased to be an operating unit in its own right in the 1980s and was wound up at the end of 1992. This was caused by British Rail reorganising the regional structure being abolished and replaced with business-led sectors. This process, known as ‘sectorisation’, led to far greater customer focus, this was cut short in 1994 when privatisation caused British Rail to split up.