The Railways Act of 1921 created the Big Four railway companies The GWR, The LNER, The LMS and The SR.
Over 100 independent railway companies had been brought under government control during the First World War but on 1 January 1923 they were merged into the Big Four companies which ushered in a period of railway excellence that was to last until nationalisation in 1948.
This map shows the railways in Britain as they were reorganised by The Railways Act, 1921, which took effect in 1923 together with a similar grouping in the newly formed Irish Free State in 1925. Why those dates? It was around 100 years since the Stockton & Darlington, the first steam worked railway to carry passengers, was opened in 1825. But this was no birthday celebration but much more of a move to ensure that railways continued to run for the following hundred years without becoming financial burdens to their owners or to the state. That was the thinking of the time. In the event, in the following 80 or so years it was all so different with further reorganisations, major closures, and financial matters taking centre stage.
Right from the start of railway development using steam locomotives in the early decades of the 19th century most railways were planned and promoted on a local basis linking nearby towns and cities - Stockton & Darlington, Liverpool & Manchester, Canterbury & Whitstable, Bodmin & Wadebridge to take a few examples. Thus hundreds of companies were established by Acts of Parliament and even with mergers right through the Victorian years, (particularly of long through routes like the Great Western which in 1876 absorbed four other companies to form one authority from Paddington to Penzance), over 120 separate companies remained as war broke out in 1914, some heading for financial problems. After Government control until 1921 an Act of Parliament compulsorily amalgamated most British companies into four large groups from 1923 and these are depicted in different colours on this map together with previous ownership. It forms a graphic record of railways in the British Isles virtually at their peak at this important time in their history.
Each map has a booklet describing the history of the railway network up to 1923