“When I was a boy, Ireland meant the Protestants; now, it means the Catholics.” Thus spoke John Beresford, a fiercely anti-catholic member of one the most powerful families in Ireland, a few years after the Union – and, incidentally, whose former power the Union gradually weakened. This statement points at both a changing definition of what Ireland was, and at the importance of outsiders' perception in the construction of identity.

This paper will examine the dynamics of this change: the new interest in demography, and the desire or refusal to count the people in Ireland, and to ascertain its religious distribution; the translation of pre-Union Ascendancy stereotypes into the post-Union parliament of the United Kingdom; and the growing construction of an alien identity, different from and potentially hostile to a supposedly unified and stable British identity – a construction which eventually found its way into the newly emerging race theories.