Snow White was the daughter of King Leopold and Queen Eva, who was born a princess. As she grew up, her mother died from an illness, and was replaced by her stepmother Regina. Years later, her father was killed and Regina took over the kingdom, ruining Snow's chances of become a kind and gentle queen herself. After Snow realises that Regina killed her father, she goes on the run in the woods and finds refuge with the Seven Dwarves while Regina sends out dark forces to destroy her. Regina eventually gets Snow to eat a poisoned apple, and she falls into a deep death-like sleep. However, true love's kiss from Prince Charming wakes her up.
Prince Charming arrives in the woods on horseback, to see seven dwarves mourning over someone. He sees a seemingly dead Snow White lying peacefully in a glass coffin. Heartbroken, Charming requests that they open the beautiful coffin so he can say goodbye to her. The dwarves oblige, and Charming kisses her. However, that kiss turns out to be true love's kiss, and Snow wakes up. The two eventually get married, when Regina suddenly interrupts the wedding. She boasts about taking away everyone's happiness and destroying it, before vanishing, causing a panic. Months later, a pregnant Snow is still worrying about Regina's threat, so Charming takes her to see a man who can see the future; Rumplestiltskin. He informs them that Regina will unleash the Dark Curse, but says that the child of Snow and Charming will return uneffected by the curse, and rescue them. In return, Snow tells Rumplestiltskin the name of the baby; Emma. On the night of the Dark Curse, Snow unfortunately goes into labour and gives birth to baby Emma. However, she and Charming realise that they are doomed unless they save Emma. Charming puts Emma into a magic wardrobe which sends her to earth while Snow, Charming and the Enchanted Forest are consumed by the Dark Curse.
In Storybrooke, she becomes cursed and forgets about her past live as Snow White. She goes by the name Mary Margaret Blanchard and is the teacher at Storybrooke Elementary School. Mary Margaret is seen teaching the class about making a birdhouse before the bell goes and as the children depart, Regina Mills arrives with Emma Swan. Neither Emma nor Mary Margaret know that they are actually mother and daughter. Regina shows a lot of hatred towards Mary Margaret, and knocks down a pile of books as she leaves the classroom. Emma stays behind to help pick up the books, and Mary Margaret tells her that Henry is at his secret castle playground. She later gives flowers to the patients at the hospital, including a comatose Prince Charming, who she doesn't recognise.
- S1, E1: "Pilot"