I don't know of any Dwane's that have immigrated to the U.S. besides my dad in the 1950's. so right now I don't see a connection. How long have you been researching? What avenues have you tried so far in your research? Also, I'm not sure Spain is as uncommon as you think. I was looking on the site ancestry.com to see I could find anything under your Edward Dewan or John Spain. There were over 2,500 Spains internationally. Good luck in all your research.