There were lieutenants of counties in Ireland until the reign of James II, when they were renamed governors.[1] The office of Lord Lieutenant was recreated on 23 August 1831.
Helen Rosemary Alison Millar: 12 June 2018 – present[7]
Deputy lieutenants
A deputy lieutenant of County Londonderry is commissioned by the Lord Lieutenant of County Londonderry. Deputy lieutenants support the work of the lord-lieutenant. There can be several deputy lieutenants at any time, depending on the population of the county. Their appointment does not terminate with the changing of the lord-lieutenant, but they usually retire at age 75.