Hmm, I don't think migrating to america was the cause of name getting to England, if anything they came over from germany with the saxons 5th C and spread from there. However we'll never know as reliable sources from that time are few and far between.

Your timeline looks a little off as well, you're going 4 generations back and you say that a man donated the land parliment was bulit on? The palace of westminster has been on that location since at least 1295 and have been in royal usage since 1016.

Just trying to clarify things!