Do you have to live in the US to sign up for the beta of Hearthstone: Heroes of WarCraft?

I've read over the Hearthstone FAQs, but unless I missed something didn't see an answer. Just that I could opt in for the Hearthstone beta via my Battle.net account.

Are gamers interested in the beta test of Hearthstone: Heroes of WarCraft required to live in the US?