Shrek is a 2001 animated comedy film from Dreamworks, about the adventures of an Ogre and his sidekick, Donkey in a fairytale universe. The first film focused on them rescuing a princess and discovering the shocking secret that she has been cursed and the only way to break the spell is "True Love".
But one question remains, who cursed the princess?
Most Likely Suspects[]
1) Witches: According to the film, Fiona recalls that when she was a child a witch cast a spell on her, turning her into an ogre every time the sun sets. However no one ever states who said witch is. It's also pointed out that witches do appear in the film's sequels but they hardly ever use their magic, leaving us to believe that neither of them has the magical capability to turn people into other creatures.
2) Rumpelstiltskin: Another likely suspect, is Rumpelstiltskin, as portrayed in the fourth film, he originally wanted the king and queen of Far Far Away to sign a waiver that will likely break their daughter's curse. It's also pointed out that he has the power to turn time and send people to alternate dimensions. How ever in the alternate reality, Fiona is still cursed so its unlikely that he has the capability to cast such a spell.
3) The Fairy Godmother: According to Puss in Boots, she is the "Largest producer of hexes and potions". In Shrek 2, she has a lot of potions that can turn people into other creatures like birds, horses and etc. It's also pointed out that her plan all along was to have Fiona and her son, Prince Charming to get married so she can rise to power and take over the kingdom. She also made a deal with Fiona's father, King Harold and his end of the bargain that their children will marry, except Shrek came along which jeopardize her entire plot. Just goes to show that God always wins when it comes to playing with destiny.