How common is Elsa?

[debijon11]

I have loved the name Elsa, since I first heard the name on the TV series Mistresses. Now almost 10 years later and four boys, I now have an opportunity to use it. Or has Frozen ruined my chances of using the name? I also like Martha.

I think Elsa is nicer than Martha. I don't think "Frozen". Could you go for Ilsa or Ilse instead - northern European spellings. Think "Casablanca".