Some readers of the NDFHS Journal may remember an article of mine; "Durham - a 19th Century Shamrock County".( Autumn 2000 ). I followed this up with a second article which was not published but I think the conclusions may be of interest so I provide a very short summary below. I am prepared to send by Email the full article and tables ( the article requires Word 2000 or later and the tables require Excel 2000 or later ): The analysis is based on the IGI 1881 Census CDs In County Durham where Irish County of Birth ( ICoB ) was recorded in the 1881 Census, the breakdown by Irish County was: Tyrone 13.0% of total Down 8.7% Sligo 7.9% Armagh 7.5% Monaghan 6.9% Antrim 6.0% Mayo 5.3% Galway 5.2% Derry 4.7% Roscommon 4.5% The above account for 70% of the total with ICoB identified By area within Durham: Most Irish on Tyneside came from the Ulster Counties ( plus Galway ) Most Irish in the wider Consett area came from the Ulster Counties ( Tyrone and Monaghan in particular ) Most Irish on Wearside were from the Connaught Counties Most Irish around Teeside/Hartlepool also mainly came from Connaught though Armagh had a strong presence in Cowpen Bewley In some Census areas there were exceptionally high proportions from individual Irish Counties: Winlaton 50% from Galway Consett 50% from Tyrone Iiveston 50% from Tyrone Tanfield 33% from Tyrone Hedleyhope 50% from Tyrone Sunderland 33% from Roscommon Monkwearmouth Shore 50% from Roscommon Stranton 33% from Sligo Cowpen Bewley 33% from Armagh Whickham 33% from Waterford West Rainton 66% from Down ( especially Comber Parish ) So if you know your ancestors were Irish ( but not where from ) and where in County Durham they settled the above may help prioritise your researches