Last summer I stayed with a family in Germany and they told me that Henke was a very German name and I know that my ancestors came from there. I do not know if the same goes for Henkes, but I would assume so. They also told me that when people immagrated into the states many of them changed spellings and pronunciations of their last names. For example my last name. We pronounce it "Hinky" but in Germany it is pronounced "Hinka". I hope this helps you out some.