 The City of London, and Middlesex, became separate counties for other purposes and Middlesex regained the right to appoint its own sheriff, lost in 1199.In the interwar years suburban London expanded further, with improvement and expansion of public transport, and the setting up of new industries.After the Second World War, the populations of the administrative county of London and of inner Middlesex were in steady decline, with high population growth continuing in the outer parts of Middlesex.