Six largely rural administrative counties based on these were among the eight primary local government areas of Northern Ireland from its 1921 creation until 1973.

[6] This process lasted from the 13th to 17th centuries; however, the number and shape of the counties that would form the future Northern Ireland would not be defined until the Flight of the Earls allowed the shiring of Ulster from 1604.

[6] The area of the modern counties of Antrim and Down was the Earldom of Ulster based on John de Courcy's 1170s conquest of Gaelic Ulaid.

[7] Between the late 13th and early 14th centuries it was subdivided into multiple shires based around centres of Norman power such as Antrim, Carrickfergus, and Newtownards.

[7] The Bruce invasion (1315–18) saw the devastation of the Earldom of Ulster and its overlordship over the neighbouring Gaelic districts.

With the murder of the last de Burgh earl in 1333, the resulting Gaelic recovery expanded Clandeboy and eroded the earldom's territory until by the 15th century only the areas of Carrickfergus and coastal enclaves in Down remained.

Baronies are now obsolete as administrative units, partially derived from the territory of an Irish chieftain.