 The Marks Tey to Sudbury section of the line opened on 2 July 1849 and ran for 5 years before being taken over by the Eastern Counties Railway on 7 August 1862.In 1862 the Eastern Union Railway and Eastern Counties Railway were amalgamated into the new Great Eastern Railway.After several years of protracted legal disputes, the Great Eastern Railway opened the section from to Shelford on 1 June 1865 and then the section from Sudbury to Haverhill on 9 August.