Actually it comes from their region Schwaben. Most of the colonizators from Germany which came in our region were from this region in Germany. And when they were asked from which country are they would say Schwaben. So for us they were Švabe. It is the same thing with early Croats in Autralia and New Zealand. They were Dellys or Dalmatians because they were mostly from Dalmatia. So  later the name of Dalmatian spread for all Croats in AU and NZ.
Goran is like Igor. Slavic Igor is russian version of nordic Ingor, Ingwar, Ivar which means defender of sea.

am talking about švab as a term for a cockroach