Interesting map of Poland under rule of King Chrobry:
Shows that White Croatia was still one of Western Slavic homelands (together with Polish and Czech/Slocak tribes) in 10th-11th century, even though already they had travelled Southward to Balkans 200-300 years earlier. I wonder what happened to White Croatia actually, why it did not become sovereign state like Poland, Bohemia or Moravia did.
Another map (from that Ancient Poland thread) also shows Croats as being still in Ukraine:
But I disagree with this map in that as representation of Western Slavs, they should have also included Slovenians and Croats, but they didn't.