Yes,
Astrid Lindgren's Ronja the Robber's Daughter books are very popular here in Finland as well! I believe the name Ronja is in the top 10 girls' names at the moment.
I've also heard that Ronja/Ronya is a male pet name in Russia, short for Ronimus (
Hieronymus) or something similar. I don't think Ronja is used as a girls' name in Russia, though.