The Office of H.M. Lieutenant is generally accepted to have begun in 1547 as a temporary military post when the military functions of the Sheriff were transferred and the Lord-Lieutenant became responsible for the county bodies of the trained bands. The trained bands had their origins in the Fyrd of Anglo-Saxon times and were the pre-cursors of the Militia of the 18th and 19th centuries.
The Lieutenancy system gradually developed around the country and it was not until after the Restoration that the move toward a Lord-Lieutenant in each County took place. Before that, senior noblemen, usually absentee, tended to hold multiple Lieutenancies and later appointed Deputies to serve locally.
The early Commissions were not for life and only lasted for the event of crisis, for which they were originated. Some Lord-Lieutenants were appointed more than once or were superseded and later reappointed. After 1588, Commissions were retained instead of being lapsed, although a change of Sovereign could result in a change of Lord-Lieutenant. The Authority for the appointment varied from time to time between the Sovereign and Parliament via the Privy Council.
The Lord-Lieutenant’s active duties were mainly to do with the raising and training of the forces of the Crown and also responsibility for the selection and administration of the Justices of the Peace. Therefore, since the early years of the 18th Century, the Lord-Lieutenant has typically been the leading Justice under the title of Custos Rotulorum - Keeper of the Rolls. Thus it evolved that the Lieutenancy was not only the arm for raising troops, but also a means of communication between the Government and the country, working through the Deputy Lieutenants in the former case and through the Justices in the latter.
Matters proceeded roughly in this way until the Cardwell reforms of the Armed Forces in the latter half of the 19th Century, when military matters were revested in the Crown and exercised through the Secretaries of State. However, to this day, the Lord-Lieutenants are Presidents or Vice-Presidents of the Territorial and Army Volunteer Reserve Association, appropriate to their County, and they continue, with the assistance of a committee, to recommend to the Lord Chancellor candidates for appointment as Justices of the Peace.
The County records show the existence of a Lord-Lieutenant and Deputy Lieutenants in Nottinghamshire early in the reign of Charles I and, on 20th April 1628, "Lieutenant of this County" William Earl of Newcastle sent to the Court of Quarter Sessions accounts signed by Gervase Clifton, Bart., H. Wasteneys, Bart., and William Cooper Esq., his Deputy Lieutenants of moneys collected and levied from the County for provision of soldiers.
In present times, Lord-Lieutenants are honorary officers officially appointed by the Crown by Letters Patent under the Great Seal on the recommendation of the Prime Minister and are appointed as "His Majesty’s Lord-Lieutenant of Nottinghamshire" although less formally known as the "Lord-Lieutenant of Nottinghamshire".
Lord-Lieutenants are the permanent representative of the Crown in the County for which they are appointed and their appointments do not lapse on the passing of a Sovereign. They are appointed by the Monarch to serve until they reach the age of 75 years.
Since 1st April 1974, the Crown may appoint one or more Deputy Lieutenants, in addition to the Lord-Lieutenant, where the size or needs or other circumstances of a County require. The Lord-Lieutenant may appoint one of them to act also as Vice Lord-Lieutenant.