In The Irish Empire Patrick Bishop looks at why, in the last four hundred years, to be brought up in Ireland meant being prepared to leave it, an Irish cultural mindset that has persisted almost to the present day. In doing so, he examines the Irish notion of separateness that goes as far back as the ancient Irish Gaels; the impact of the nineteenth-century Potato Famine on the pattern of Irish emigration; the early colonization of America and how the Irish provided the muscle that built the infrastructure of a new nation; the transplanted tension between Protestants and Catholics in their new lands; the enduring power of the Catholic Church; and the popular identification of British oppression as the engine which drove so many Irish abroad.