Unsurprisingly, given its name, Louth is the smallest county in Ireland. Before the coming of the Normans, along with Monaghan and Armagh it formed part of the Gaelic kingdom of Oriel. The leading family in the area at that point were the O'Carrolls, though the name is now quite rare in the county. Prince John annexed the area to the English crown in 1185 and from that point on the dominant influences were English and Norman; Louth was part of the Pale, the belt of land surrounding Dublin where the jurisdiction of the English crown remained undefeated.
The Norman influence was responsible for the development of two relatively large towns close together, Dundalk and Drogheda. This urbanisation, unusual by Irish standards, may also partly account for the fact that by the middle of the nineteenth century the most densely populated area in Ireland, outside Dublin, was the Armagh-Louth-Monaghan area.
The most beautiful part of the county is the Cooley peninsula, where the medieval harbour town of Carlingford overlooks a deep fjord with jagged mountains at its back.
Surnames associated with the county include Belton, McArdle, Hamill, Dowdall, Duffy, Quigley, O'Hagan, O'Hare and Corrigan.