 Six Declaration of Independence signers were of Irish and Ulster Scot descent, with one signee Charles Carroll of Carrollton, being the only Catholic signer.However, conditions in Ireland (under Protestant control and British sovereignty) -- especially the Great Famine—caused many Catholic Irish to emigrate in the mid-19th century.An Irish immigrant, having suffered through an arduous overseas journey, would have been thrust into a difficult and unfamiliar situation, as many were poor and unused to American customs.