In Scotland , the Local Government ( Scotland ) Act 1973 established a similar system of two-tier regions and districts in 1975 -- this was also replaced by a system of unitary council areas in 1996 . In Scotland , where this Act did not apply , the Local Government ( Scotland ) Act 1973 regionalised local government with a system of two-tier regions and districts in 1975 -- this was also replaced by a system of unitary council areas in 1996 .