Hello Francis,
I wonder if the Rollingers and the Roellingers all have ancestors from the Tyrol of Austria, as do the Drollingers and the Trollingers. Some of my ancestors come from the town of Fehrbach, in Germany south of Kaiserslautern. After its population had been destroyed by the Thirty Years War (1618-1648) it was conquered by the French under Louis XIV, who invaded that region in 1672, and subsequently it was repopulated by French from Picardie and Austrians from Tyrol. Alfons Helfrich, a distant cousin of mine in Germany, wrote a book about that town in German.
I suppose the Polish and Hungarian Rollingers settled in those regions when they were part of the Austrian Empire.
I used to have cousins, Frank and Leo Leichtman, who lived on a farm near Sioux Falls, I think on the northwest side.
They are related to me through my great-grandfather Michael Leichtman, who was born in 1831 at Zweibruecken, south of Kaiserslautern on the French border, and who came to Spillville, Iowa in 1851. I live in Cedar Falls Iowa, where several Rollingers live.