We explore predictions from three sociological models linking excess Irish mortality in England and Wales with urban and regional patterns of settlement and mortality. The analysis is prospective, of urban residents aged 25-74 in a 1 per cent sample of the 1971 Census of England and Wales, linked with death certificates from 1971-1985 (the ONS Longitudinal Study). Analysis is by multilevel modelling of probabilities of death.The association of past Irish immigration with contemporary regional mortality is confirmed. However Model 1, suggesting that excess Irish mortality is solely a regional effect related to the economic history of the north and west, is rejected. Model 2, suggesting that excess Irish mortality is due to political and religious differences which have tended to disadvantage this group similarly across regions of England and Wales, is supported. Model 3, suggesting that the economic model (1) and cultural model (2) interact, creating sharper political and religious divisions and greater excess Irish mortality in the north and west, is rejected.