The Caledonian Railway was a major Scottish railway company. It was formed in the early 19th century and it was absorbed almost a century later into the London, Midland and Scottish Railway, in the 1923 railway grouping, by means of the Railways Act 1921. Due to legal complications this did not take place on 1 January 1923 when the majority of the amalgamations took place, but was delayed until 1 July 1923 (along with the North Staffordshire Railway).