The Grimms say Perchta or Berchta was known "precisely in those Upper German regions where Holda leaves off, in Swabia, in Alsace, in Switzerland, in Bavaria and Austria."[REF]
According to Erika Timm, Perchta emerged from an amalgamation of Germanic and pre-Germanic, probably Celtic, traditions of the Alpine regions after the Migration Period in the Early Middle Ages [REF].