This is "Jona Vark" by Gypsy & the Cat.
I've had it firmly stuck in my head for the last few days since I saw the video on a music channel, so I thought I'd post it.
This post is also intended to help those who have been trawling google in a fruitless attempt to find a song they've heard but don't know the name of, furiously typing in "her name is joan of arc lyrics", but to no avail...... How very confusing. Poor dears. I hope this page comes up on google to enlighten them.