At its inception, the LMR's territory consisted of ex-LMS lines in England and Wales. The
Mersey Railway, which had avoided being
"Grouped" with the LMS in 1923, also joined the LMR. The LMR's territory principally consisted of the
West Coast Main Line (WCML), the
Midland Main Line (MML) south of
Carlisle, and the
ex-Midland Cross Country route from
Bristol to
Leeds. During the LMR's existence there were a number of transfers of territory to and from other regions. The major changes were: • In 1949 the
London, Tilbury and Southend line, which was completely cut off from the rest of the LMR network, transferred to the
Eastern • Also in 1949, the isolated from the rest of the LMR ex-LMS
Northern Counties Committee railway lines in
Northern Ireland were bought by the
Ulster Transport Authority. • In 1958 a major re-drawing of the regional boundaries took place. LMR lines in South Wales and south-west of Birmingham were transferred to the
Western; lines in Lincolnshire and South Yorkshire went to the Eastern; in North and West Yorkshire to the
North Eastern. In return, the London Midland gained the former
Great Central Railway laying outside Yorkshire and Lincolnshire. • In 1974, the
Chiltern Main Line from
London Marylebone to and was transferred to the LMR from the Western Region. == Locomotives and rolling stock ==