20th Century
The Territorial and Reserve Forces Act 1907 established County Territorial Force Associations, of which the lieutenant was to be head, styled president of the county association. It restated the combination of counties and counties corporate as lieutenancy counties.
In 1921, with the establishment of Northern Ireland, lieutenants continued to be appointed through the Governor of Northern Ireland to the six counties and two county boroughs. The creation of the Irish Free State in the following year saw the remaining county lieutenancies in Ireland abolished. In 1973 the counties and county boroughs were abolished as local government units in Northern Ireland, and lord-lieutenants are now appointed directly by the Queen to "counties and county boroughs... as defined for local government purposes immediately before 1 October 1973". In 1975 the term lord-lieutenant officially replaced that of lieutenant.
Local Government reform in England in 1965 led to the appointment of lieutenants to Greater London and Huntingdon and Peterborough, and the abolition of those of the County of London, Middlesex and Huntingdonshire.
A more fundamental reform of local government throughout England and Wales (outside Greater London) created a new structure of metropolitan, non-metropolitan and Welsh counties in 1974. Section 218 of the Local Government Act 1972 that established the new system stated: "Her Majesty shall appoint a lord-lieutenant for each county in England and Wales and for Greater London..." The Act appears to be the first statutory use of the term "lord-lieutenant" for lieutenants to counties.
Existing lord lieutenants were assigned to one of the corresponding new counties wherever possible. Where this could not be done, the existing office-holder became a lieutenant of a county, junior to the lord-lieutenant. For example, the Lord Lieutenant of Montgomeryshire was appointed Lord Lieutenant of Powys, with those of Breconshire and Radnorshire each being designated as simply "Lieutenant of Powys". This measure was temporary, and no lieutenants have been appointed in this way since 1974, although the power still exists.
In 1975 counties ceased to be used for local government purposes in Scotland. The Local Government (Scotland) Act 1973 replaced the counties with regions, and each region was to have one or more lord-lieutenants appointed. The areas to which they were appointed approximated to the counties and were based and were defined in terms of the new local government districts.
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