Katherine Anne "Kitty" Pryde was born in Deerfield, Illinois to Carmen and Theresa Pryde. Of Jewish descent, her paternal grandfather, Samuel Prydeman, was held in a Nazi concentration camp during World War II.
Meeting the X-Men Kitty started to have headaches at age thirteen, headaches which signaled the emergence of her mutant powers. She was approached by both the X-Men's Charles Xavier and the Hellfire Club's White Queen, Emma Frost, both of whom hoped to recruit her for their respective causes. Kitty was unnerved by Frost, observing that the White Queen had looked at her as if she were "something good to eat." She got along better with Xavier and the three X-Men who escorted him to his meeting with her and her parents, becoming fast friends with Ororo Munroe. Ororo told Kitty who she really was and about the X-Men, which made the teenager even more enthusiastic about attending Xavier's school.
Their conversation was cut short, however, when they (along with Wolverine and Colossus) were attacked by armored mercenaries in the employ of Frost and the Hellfire Club. The X-Men defeated their assailants, but were subdued by the White Queen's telepathic powers immediately after. In the confusion, Kitty had become separated from the X-Men and therefore was not captured along with them. She managed to contact Cyclops, Phoenix, and Nightcrawler. With the help of Dazzler and Pryde, those X-Men rescued their teammates and Xavier (who had also been captured).
The White Queen appeared to perish in the battle, which meant she was no longer competing with Xavier for the approval of Kitty's parents. Unfortunately, Kitty's parents hadn't heard from her in more than a day, because during that time she was first being pursued by the Hellfire Club's men and then working with the X-Men to save their friends. All they knew was that Kitty had left with Xavier's "students" to get a soda, there had been reports that the soda shop had been blown up, and that Kitty had been missing since. Understandably, they were angry at Xavier when he finally returned with Kitty in tow. At first, it seemed like there was no chance of Kitty being allowed to attend the school and join the X-Men. Phoenix then decided to use her considerable telepathic power to erase the memories of Kitty's parents and plant false ones, resulting in a complete shift in their attitude towards Xavier. Questions concerning the morality of tampering with minds in such a fashion aside, Kitty was then allowed to enroll at Xavier's school with her parents' blessing. She was the youngest person to join the X-Men up to that point.
Joining the X-Men During her teen years, Kitty fostered a number of close relationships with others at the school and in the X-Men. She developed a crush on Colossus and became close friends with his little sister Illyana Rasputin. Initially uneasy around Nightcrawler and other mutants with physical deformities, Kitty finally overcame her fears and became close friends with him. Kitty also befriended Lockheed, a highly intelligent alien resembling a dragon, who followed her home after a mission in outer space. Lockheed is extremely loyal to Kitty, and the two of them share a psychic bond. Wolverine became something of a mentor to Kitty despite his usually gruff personality. Storm came to view Kitty as the daughter she never had.
Kitty was later assigned to the New Mutants, a team of younger mutants established in the absence of the X-Men while they were in outer space. Kitty convinced Professor Xavier to allow her to remain a full member of the X-Men on the basis of her high intelligence, maturity, and the fact that she was already a fully-trained member of the team. During this time, Kitty began to "date" Colossus, but this did not last long for a major legal reason. Jim Shooter, the editor-in-chief at the time, disapproved of "the idea of a 19 years old boy sleeping with an underage girl."  This is due to not just statutory rape laws, but also a general cultural repulsion in many countries for anything hinting at child abuse. Kitty in fact had directly propositioned Colossus in X-Men #165, when they both were infected with Brood embryos, but due to her being underage (see statutory rape), Colossus refused, saying, "However, little one, you are not older." He did, though, share one passionate kiss with her before refusing, as a message of, "but if you were older...."
Because of Jim Shooter's disapproval of this budding relationship, Colossus developed feelings for an alien woman named Zsaji whom he met on the Beyonder's planet in the first Secret Wars. Colossus' feelings toward Zsaji were primarily a side effect of her own unique healing abilities, which she had used on him after he became injured. Regardless, Colossus' feelings were real and he returned to Earth consumed with grief after Zsaji's death. He admitted to Kitty that he loved Zsaji, which hurt her deeply and ended the budding relationship. Kitty had made good friends with a local boy from Salem Central named Doug Ramsey around this time, but her feelings for him never went as deep as his for her, and they never actually dated, though they remained close, even more so after Doug's status as a mutant was revealed and he joined the New Mutants under the codename Cypher. They remained friends until his death some time later.
Ogun During the 1985 Kitty Pryde and Wolverine miniseries, Kitty is possessed by a demon, the ninja Ogun. Ogun psychically bestows upon Kitty a virtual lifetime of martial arts training. Kitty is able to resist Ogun's influence with Wolverine's help and the two form a strong teacher/student bond. Kitty returns to the X-Men, no longer the innocent they once knew, and officially adopts the codename Shadowcat.
Morlock Massacre Kitty was badly injured by Harpoon during the Mutant Massacre story arc, with the result that she lost control of her power and was stuck in an intangible state. She was rushed to Muir Island along with other surviving casualties of the Massacre to be tended to by Moira MacTaggert. MacTaggert was able to keep Kitty's condition from deteriorating to the point where she completely lost physical substance and ceased to exist, but wasn't able to do any more to help her. At this time, Kitty's natural state was to be intangible. Where she once had to make a conscious effort to phase, she now had to make a conscious effort to solidify and stay solid. She was saved by Reed Richards, Mr. Fantastic of the Fantastic Four, but not without trouble. The X-Men had gone to Richards for aid, but he had initially refused because he was not sure he would be able to help (Reed was in a struggle with the rest of the Fantastic Four about their origins. They thought that Reed deliberately caused their accident which turned them into the Fantastic Four, thus making him very uncertain about his personal motives and abilities). Having nowhere else to go, the X-Men turned to Richards' enemy Dr. Doom. This created a moral dilemma for both the X-Men and the Fantastic Four. Both teams fought each other because the Fantastic Four were trying to stop the treatment while the X-Men were determined to save Kitty's life. In the end, both the personal crisis of the Fantastic Four and the life of Shadowcat were saved. It was Franklin Richards, with the help of Lockheed, who brought both teams to their senses. Kitty has since recovered from this state and now has full control over her power again.
Excalibur Among the others injured and brought to Muir Isle were Colossus and Nightcrawler, although Colossus left the United Kingdom shortly after being released from MacTaggert's care to join the rest of the X-Men on their mission to battle the Adversary. The X-Men sacrificed their lives to defeat the Adversary, and the battle was televised and broadcast across the world. The X-Men were resurrected later, unknown to the world at large, but chose to keep a low profile and perpetuate the belief that they were still dead. This strategy was enforced to more effectively fight their enemies. This meant avoiding contact with friends and family, including Kitty. Thinking the X-Men were dead, Kitty and Nightcrawler joined Rachel Summers, Captain Britain, and Meggan to form the Britain-based team Excalibur. During her time with Excalibur, Kitty developed a crush on Professor Alistaire Stuart which went unreciprocated since Alistaire was attracted to Rachel. Later, she was romantically involved with former Black Air agent Pete Wisdom, but they ended their relationship a short time before Excalibur disbanded.
After Excalibur's dissolution, Shadowcat, Nightcrawler and Colossus returned to the X-Men. Yet as soon as they returned, they faced a group of imposters following Cerebro, in the guise of Professor X. During the six-month gap, Kitty visited Genosha. Whatever she experienced there is unknown (although presumably connected to her father, living on Genosha at the time), but it had a profound effect on her. She cut her hair and began to act rebelliously, also using one of Wolverine's bone claws broken off during battle as a weapon. Kitty remained with the X-Men for a while before leaving after the apparent death of Colossus. Trying to give herself a normal life, she attended the University of Chicago. During this time, her father was killed when Cassandra Nova’s Sentinels destroyed Genosha. She was also kidnapped by William Stryker, but the X-Treme X-Men team helped her escape and she assisted them on several missions. At some point between the end of the six-month gap and leaving the X-Men, Kitty also came into possession (possibly by theft) of the Destiny diaries, for reasons unknown.
Back To The X-Men At the start of Joss Whedon's run on Astonishing X-Men, Kitty once again rejoins the X-Men, despite having extreme reservations about working with the former White Queen, given their history. However, this was the primary reason why Frost herself wanted Kitty on the team, as a sort of "safety" should Frost ever revert to type. Frost reasoned that the person who trusted her the least would be most likely to spot such behavior. On one of the team's first missions, Shadowcat discovered Colossus was alive. After some initial awkwardness, Kitty and Peter resumed dating.
In the "Hellfire" arc, the latest incarnation of the Hellfire Club begin an assault on Xavier's School. Kitty fulfilled the role that Emma Frost envisioned, personally taking down Frost and imprisoning her, only to fall under a telepathic delusion created by Hellfire member Perfection, who claimed to be the true, unreformed Emma Frost. Under this delusion, Kitty was made to believe that she and Colossus had conceived a child, which was later taken away by the X-Men because its potential mutant abilities were supposedly dangerous. Kitty reacts in the delusion by attempting to rescue the child from a near-inescapable "box" in the depths of the school, unaware that in reality she is freeing an alien entity, "Stuff," who contains the trapped consciousness of Cassandra Nova, the apparent ringleader of this new Hellfire Club. A newly awakened Cyclops revealed that the new Hellfire Club, including Perfection and Nova, are actually mental projections created by a piece of Cassandra Nova's consciousness, which became lodged in Emma's mind during the X-Men's last confrontation with her. As Cyclops killed the mental projections, Emma tried to force Kitty to kill her to get rid of Nova. Undeterred, Cassandra Nova switched her focus to attempt to transfer her mind to Hisako Ichiki. It appears that Nova did not succeed, as the team was transported to S.W.O.R.D.'s air station en route to Ord's Breakworld for the "Unstoppable" arc that concludes Whedon's run on Astonishing X-Men.
As the team prepares to end the confrontation with the Breakworld leader, the team splits up--with Kitty on the team appointed to stop the missile pointed at the earth. Kitty phases into the missile to disrupt its circuitry noting that it is composed of the same material as the rest of Breakworld, making it difficult and exhausting for her to phase through. After phasing for a mile into the missile, Kitty finds the center only to discover it empty. The missile is fired, causing Kitty to pass out inside of it as Beast discovers too late that due to its shape, trajectory, and lack of internal circuitry, the Breakworld's weapon is not a missile, but a bullet. As the bullet hurtles toward Earth, Kitty lays unconscious within it. The story is ongoing.
Kitty Pryde recently appeared with Colossus in the "Blinded by the Light" arc in X-Men. They are the two X-Men left to look after the students while the rest of the X-Men leave for Mystique's home in Mississippi to check up on Rogue, during which they are ambushed by the Marauders. Kitty and Colossus, meanwhile, attempt to protect the students from a faction of the Marauders led by Exodus. It is revealed over the course of the story that Kitty, worried of the Destiny Diaries' safety, devised a plan with Cyclops and Emma Frost to hide them and have Emma wipe the location from her mind. The location could only be revealed by a code word spoken to Kitty. The arc concludes with a battle between Iceman and Cannonball against the Marauders for the diaries, during which they are destroyed by Gambit.
Kitty does not appear in the X-Men crossover event X-Men: Messiah Complex.
In Uncanny X-Men #496 it is mentioned Colossus has recently lost the woman he loves. Colossus says that his parents, his sister, and Katya (Kitty) are all things that being an X-Man has cost him. No explanation has been given for the character's disappearance and it is currently unknown if Kitty is either dead or missing.