Irish Celebrity Girl

However, it had been recognised that the estimated numbers of the Irish diaspora may be highly inaccurate; one reason is that the majority of ancestral censuses conducted within the United States and Canada record self-reported ancestry, which is often unreliable. The majority of people living within immigrated populations (i.e. Australia, United States, Canada etc.) are of mixed ancestry due to decades, at times centuries, of inter-marriage with other immigrants or indigenous populations, hence claiming one specific ancestry is often personal preference or perceived ancestry rather than fact.
The author Jim Webb suggests that a large number (he suspects near half) of those claiming Irish-American ancestry, especially among Protestants, may be Scots Irish (that is, descendents of Scottish people who populated the Irish province of Ulster)