of 1919, and a coal strike in 1921, both of which caused considerable damage to the M&GNJR. The national general strike took place in 1926. Grouping of the railways Wartime control of the railways ended on 15 August 1921, and the government passed the Railways Act 1921, which had the effect of transferring most of the railways of Great Britain into one of four new large companies, in a process referred to as the "grouping". The Midland Railway was transferred to the new London, Midland and Scottish Railway (LMS), and the Great Northern Railway (as well as the Great Eastern Railway) were transferred to the new London and North Eastern Railway (LNER). The M&GNJR remained unchanged, now jointly owned by the LMS and LNER. The rivalry with the GER was naturally at an end. The change took place formally on 1 January 1923. The long-distance express trains were reinstated progressively, and the LNER particularly emphasised to traffic. Holidays at the seaside increased in popularity very considerably after the war, and as well as trains to and from the area, local services for holidaymakers staying in the area were enhanced in the season. However road competition, both for goods and passengers, began to take a serious toll as roads were improved. at the same time a general depression in the agricultural sector harmed M&GNJR income. Incorporation into the LNER The Midland and Great Northern Joint Railway had retained its identity at the grouping of the railways in 1923. In the mid-1930s there was good cooperation between the LMS and the LNER and in 1935 it was agreed that the LNER should manage the operational aspects of the M&GNJR system, though maintaining its independent identity. This took effect from 1 October 1936. The system consisted of , of which 40% was double track. World War II and after In 1939 World War II started, and once again most long-distance expresses were suspended; staff were called up or volunteered in the services. However the focus of defence, evacuation of children, and later the D-day landings was the south coast, not the east. The war ended in 1945. The railways were run down during the war and the government passed the Transport Act 1947, so that the railways became nationalised at the beginning of 1948, forming British Railways (BR). The long distance and holiday trains began to be restored, and holiday camp facilities became