My Irish ancestor, Matthew Green(e) settles in Hartlepool in county Durham, marries Catherine Hanley there in 1866 and is listed in at least 3 censuses as coming from "Ireland". One census specifies Sligo, Ireland. The 1911 census states he is from "Seaforth" in County Durham, which I hoped actually referred to a place in County Sligo. I have not been able to find any such place in Ireland. Can you?