Cos. Cavan, Fermanagh and Monaghan
The three counties of Cavan, Fermanagh and Monaghan made up the south-western part of Ulster, bordering on the mountains of Connaught and the lowlands of Leinster and the Pale. They formed an important strategic area which was, until the end of the sixteenth century, controlled by Gaelic Irish families of McGuire or Maguire (in County Fermanagh), O’Reilly (in County Cavan) and McMahon (in County Monaghan).
