Distribution of Family Names

There's a nifty application that provides you with the distribution of last names in the United States and Canada. I looked up some of my grandparents and great-grandparents surnames. Not surprisingly, Taylor is the most common name.In regards to my family history research, however, Taylor is not really our family name. Supposedly my great-grandfather was adopted by Taylors because his parents were killed, though we have never confirmed this. His surname was Miller or Muller, and he was born in Wisconsin. Ironically, the one great-grandparent I have that was born in the United States is untraceable! Whereas in Norway I was able to trace branches of the parental line going back to the early 1600's. In Canada and England I've gone back to the 1700's.