My Bowed Psaltery and Mountain Dulcimer playing, tunes I'm working on playing on the Bowed Psaltery, and video by other people working on the same project. I have been playing the BP and MD since 1972. Please visit my member page on "Psaltery Strings" web site and Friends of the Mountain Dulcimer (FOTMD)..
The Chromatic Streichpsalter I play was developed from some simple Kantle type box harp bowed even possibly with just a rosined stick with a scale only on one side. In "Germany" it became a much larger instrument called the Violin - Zither, it has the individually bowed strings and strings arranged as strum chords. So the short answer to your Question is "Germany" - but where? Before German Unification Germany itself was over 210 autonomous Kingdoms, Bishoprics, etc. Austria, Switzerland, and many other countries had large German minorities. The Bowed Psaltery is more popular today than its ever been and I've enjoyed playing it for over 50 years!