The hauntingly beautiful background music in the movie was mostly Norwegian folk songs - Bla Tonar Fra Lom & Jenta I Saueflokken and although, the "Plain People" in the movie appear to be something like Amish or Mennonites - there were no Norwegian settlements of this kind in the US. Most of these groups came from Germany & Switzerland. Most Norwegians coming to the US during this time period were Lutherans. Also, the hymn they sing during the barn religious ceremony was sung in Norwegian.
David Carradine speaks like his role in Kung Fu, Kwai Chang Caine, often during his performance.