<P> In 1864, Stefan "hadn't yet learned the careful control that rules his life now" and was an avid consumer of human blood, which was considered a "dark past" by Zap2it . Of his blood addiction, Wesley said: "It's awesome . It's a drug . He's a drug addict . I get to play a drug addict, which I love . I'm going back to his days of usage, heavy usage . When I'm in my lustful state, it's so much fun . I felt like I got to play a role that I'd never played before . I felt like I was doing something different . I just love it, and I hope it comes out the way that I envisioned ." The show's executive producer Kevin Williamson revealed that he was "looking forward to Stefan eventually falling off the wagon and drinking human blood again" after spending decades of consuming only animal blood . Wesley said "everybody has a dark side, especially a vampire, and it'd be unrealistic not to explore that". Stefan became addicted to human blood again, but got it under control with the help of Elena, who began letting him feed off her in small amounts to build up discipline . </P> <P> However, in the show's third season, Stefan's addiction returned . His humanity was taken away by Klaus, and the audience met "The Ripper", his "bloodthirsty, ruthless alter - ego who had previously only been legend" according to Zap2it, who found "this sociopath version of our hero far more compelling than his usual compassionate martyr self". Wesley, who enjoyed "Ripper Stefan" more, said it "bums me out" when Stefan quit human blood again . He said "Good Stefan doesn't feel as natural in terms of what I want to be doing on screen, and what I want to be saying . I feel a little stifled, myself, whenever he's resisting the urge to do vampiresque things ." </P> <P> Stefan Salvatore was born on November 1, 1847 and raised in Mystic Falls, Virginia to Giuseppe Salvatore and Lily Salvatore . Stefan is the younger brother of Damon . When Stefan and Damon were human, they were very close and were best friends in life . Damon always confided and trusted in Stefan and they always defended each other, especially to their father, and was fiercely loyal to him . However, this all seemed to change when Stefan and Damon fell in love with the same girl, Katherine Pierce, who turned out to be a vampire . Stefan fell deeply in love with Katherine before finding out she was a vampire . Katherine, however, compelled Stefan to not be afraid, also to keep her secret and go on as they were . It was also revealed that Katherine compelled Stefan to drink her vampire blood against his will . Damon, on the other hand, drank Katherine's blood willingly, wanting and desiring the immortal life in order to spend an eternity with Katherine . In 1864, Stefan was turned into a vampire after being shot by his father, Giuseppe, along with his brother, Damon with Katherine's blood in his system, before accidentally killing his father during a visit to tell him that he was going to let himself die . Damon, who turned into a vampire as well, promised Stefan an eternity of misery as he was angry that Stefan had forced him to turn and jealous that Katherine had also turned Stefan . A newborn vampire with uncontrollable blood lust, Stefan was unable to resist the temptations of human blood and became severely out of control and addicted (later on known as the Ripper) to the blood, killing many people because of his lack of control and extreme bloodlust . However, Stefan learned to change his ways when he was taught to control it by a vampire named Alexia "Lexi" Branson, who later on became Stefan's best friend and companion . In 1942, Stefan enlisted in the Army to fight in World War II (4x08 "We'll Always Have Bourbon Street"). After decades of absence from the town he called home, Stefan returned to Mystic Falls to visit his home and Zach . On May 23, 2009, Stefan heard the Gilbert's car accident at Wickery Bridge . It was then and there that Stefan fatefully encountered Elena Gilbert for the first time . After only being able to save Elena, Stefan noticed that she looked exactly like Katherine . </P> <P> Stefan and Elena begin a relationship and he revealed to her that he is a vampire . However, Damon returns to Mystic Falls, too, and also falls in love with Elena . Further on in the series, Damon and Stefan start to bond as brothers again and it becomes apparent that they do love each other . Because of his addiction to human blood, Stefan only drank animal blood in the beginning of the series, which made him weaker than other vampires . In season two, Stefan starts to take small amounts of Elena's blood each day to mitigate its effect on him and to increase his strength . When Katherine returns it is discovered that she had always loved Stefan and not Damon; however, Stefan is in love with Elena and not interested in Katherine . Stefan starts to build a friendship with Caroline Forbes after she is turned into a vampire . After Klaus gives Stefan his blood to save Damon from a werewolf bite, he turns Stefan into a Ripper again . </P>

When did stefan turn his humanity back on