It's the first time a woman has won the award in over 50 years. Here's the complete list of this year's winners.
The film, which received mixed reviews from critics, takes the Grand Prix and will hit theatres in September.
It's the second Palme d'Or for Ken Loach, who also won ten years ago for 'The Wind That Shakes the Barley.'
Exclusive Video: Jodie Foster and actor Jack O'Connell explore the themes of their smart new thriller.