Below the regional level, all of England is divided into 48 ceremonial counties. These are used primarily as a geographical frame of reference and have developed gradually since the Middle Ages, with some established as recently as 1974. Each has a Lord Lieutenant and High Sheriff; these posts are used to represent the British monarch locally. Outside Greater London and the Isles of Scilly, England is also divided into 83 metropolitan and non-metropolitan counties; these correspond to areas used for the purposes of local government and may consist of a single district or be divided into several.