In 1865, part of Castleton was transferred to the newly created Municipal Borough of Rochdale, and following local government reorganisation in 1894, Castleton, though lying wholly within the administrative county of Lancashire, remained divided on this basis, forming two local government districts; "County Borough of Rochdale" and ""Castleton-by-Rochdale"". Castleton-by-Rochdale was renamed to "Castleton Urban District" in 1896, and four years later in 1900, was abolished (as part of a mutual agreement between local councillors) split and transferred to the neighbouring Rochdale and Heywood local government districts.