McGrath, I think that default designation came about, not because of current numbers, but because of the fact that the original colonies (not including what used to be a part of Mexico) were English colonies. The wave of German immigrants came after that. What is now the US developed it's collective identity as being "English" (Anglo) in its early days and it doesn't seem to have lost that yet.
katlaughing, it could be. Were Bermuda and Barbados on the same trade route?