≪I wonder if the English will-nill forms were invented to translate 'nolens volens' or if they're native. ≫ Webster's Third Unabridged gives the etymology as "alter. of 'will he nill he'" with no reference to any non-English root. OED probably has more. The combination appears to be native. "Will" of course is closely related in meaning and spelling to the German "Wille", and "nill" may derive from either French "ne" (not) or German "Nil" (nothing, zero). 'Not as willed' or 'against the will' is the evident meaning.