Irish-American Witchcraft: Irish Fairies in America
I wrote previously about the Irish Gods in America and mentioned that some people do see the Gods as anchored in one terrestrial space; possibly the second most common thing I hear as an Irish-American pagan is that the aos sí, the fairies, are similarly limited to Ireland and historically Celtic lands. I can only speak here to my own experience and what I have found in studying different folklore, which is that where people from a culture go, their spirits also go.
One school of thought on this is simply that the Otherworldly folk appear to people in ways that those people can best understand; another view is that the spirits are influenced by the belief of the people. Personally, I tend to think that while some types of spirits are indeed sedentary, others are pulled or drawn to where the people who honor and offer to them are.
When the Norse settled Iceland, for example, they found alfar and huldufolk there just as there had been in their old home territories. The Wild Hunt is seen in American skies just as in European, although they are more commonly known as Ghost Riders here. The areas of America heavily settled by the Irish and Scotch-Irish, like Appalachia, have local folklore that includes traditionally Irish spirits like the Banshee and WillotheWisp. In a folklore journal from 1894, we find an article about an area of Massachusetts local belief in fairies and pixies, the former being lucky and the latter malicious. In all these examples, the people clearly felt it perfectly natural and normal to see and experience the types of Otherworldly spirits from their homelands even in these new places.
http://www.patheos.com/blogs/agora/2015/09/irish-american-witchcraft-irish-fairies-in-america/