Ireland - Counties listed by Density of Population

County Area (kmē) Population Number per kmē Dublin 921 372,773 405 Armagh 1254 232,393 185 Louth 820 128,240 156 Monaghan 1,294 200,442 155 Down 2448 361,446 148 Cavan 1,931 243,158 126 Antrim 2844 356,014 125 Limerick 2,686 330,029 123 Cork 7,457 854,118 115 Derry 2074 222,174 107 Longford 1,091 115,491 106 Tipperary 4,303 435,553 101 Roscommon 2,547 253,591 100 Tyrone 3155 312,956 99 Sligo 1,836 180,886 98 Kilkenny 2,061 202,420 98 Leitrim 1,588 155,297 98 Carlow 896 86,228 96 Fermanagh 1691 156,481 93 Clare 3,147 286,394 91 Laois 1,719 153930 90 Waterford 1,837 160,232 87 Wexford 2,352 202,033 86 Meath 2,342 183,828 78 Westmeath 1,838 141,300 77 Offaly 2,000 146,857 73 Galway 6,148 440,198 72 Mayo 5,585 388,887 70 Kildare 1,693 114,488 68 Wicklow 2,024 126,143 62 Kerry 4,746 293,880 62 Donegal 4,841 296,448 61

* Derry or Londonderry. Both names are in use.

Sources:

Irish Historical Statistics
Population 1821-1971
edited by W. E. Vaughan and A. J. Fitzpatrick
Royal Irish Academy - 1978