Although Blunt was born in the UK, she became a naturalized citizen of the US in 2015 and holds dual citizenship.
As a child, Blunt worked through a stutter, which actually increased her interest in performing. "It started quite young, because it was the only tool I had to speak properly. I was that kid, upstairs in my room, trying out stuff in the mirror. But I'd never tell anyone about it."
Blunt's first professional role came at age 18, when she played Dame Judi Dench's granddaughter in the play The Royal Family.