James and Lily Potter

James Potter and Lily Potter (née Evans) are the deceased parents of Harry Potter.

James
James Potter was born c. 1958 in Britain. He is described as having hazel eyes, a slightly longer nose than Harry's, but otherwise the same thin face, same hands, same untidy black hair sticking up at the back, and (nearly) the same height as Harry during their school days. He attended Hogwarts c. 1969 to c. 1976 where he was in Gryffindor and his best friends were Sirius Black, Remus Lupin and Peter Pettigrew. Sirius fell out with his own parents when he was around sixteen and ran away to move in with James and his parents until leaving school. He often visited the Potters, who regarded him as a "second son." James was an only child and his parents were quite elderly when he was born, even by wizarding standards; as a result, he was quite pampered.

He was described by another classmate Severus Snape as "exceedingly arrogant", by Remus as "the height of cool" and by Sirius as sometimes an "arrogant little berk". Scenes from James's time at Hogwarts have shown him behaving as a bully towards Snape, but he became a more mature individual before the end of his schooldays. He had the habit of hexing anyone who annoyed him and was more skilled at magical duelling in his fifth year than Snape, despite himself describing Snape as being famous for his ability with the Dark Arts. After seeing Snape's recorded memories of James, Harry agreed with Snape's assessment of his father's arrogance, and the revelation left Harry deeply depressed and disheartened. In defence of their "bullying", Sirius insisted that Snape had a mean streak and was not the "innocent victim" he appeared to be, and that James hated Snape for his infatuation with the Dark Arts.

James was a brilliant student, and in Harry Potter and the Philosopher's Stone, was mentioned to have become Head Boy (though in OotP it is said that Lupin became prefect, not James). He was also a player on the Gryffindor Quidditch team. There was considerable confusion over whether James was a Seeker or a Chaser but Rowling confirmed that James was a Chaser. He was shown playing with a Golden Snitch outside of games and practices, ostensibly to show off. He similarly had a habit of rumpling up his hair to produce the effect that he had just stepped off a broomstick. James and Sirius were apparently popular students, ingenious pranksters and very witty. Madam Rosmerta of the Three Broomsticks pub in Hogsmeade, once talked fondly of how the two boys used to come into her bar, flirt with her, and make her laugh.

Lily
While at Hogwarts, James met his future wife Lily Evans (born (c. 1958 - d. October 31, 1981), who was also in his year. Lily was described as having startlingly green, almond-shaped eyes and thick, shoulder-length dark red hair. She was described by Professor Slughorn as having a natural and intuitive ability at Potions, being cheeky, but always seeing the good in others. She was, according to Slughorn, very brave, very funny and very charming, and he could not imagine that anyone who met her would not have liked her. She became a member of the Slug Club, which was run by Slughorn for promising students. Lily was very pretty, and it is evident that James was very taken with her, at least since their fifth year. Lily was Muggle-born, and at home, her sister Petunia despised Lily for being a witch and saw her as a "freak", possibly because she was jealous of how their parents favoured Lily. Petunia told Harry in Harry Potter and the Philosopher's Stone that, "But for my mother and father, oh no, it was Lily this and Lily that, they were proud of having a witch in the family!"

Lily was Head Girl when she was in her final year. For most of the time they were at Hogwarts, Lily appeared to have regarded James as an arrogant bully and she and James addressed each other only by each other's surnames. James was shown doodling Lily's initials during an examination in their fifth year, while Sirius recalled that he couldn't resist showing off (and making a fool of himself) whenever she was around. However, Lily defended Snape against James's bullying (at least until Snape called her a "Mudblood") and expressed contempt for his behaviour, looking at him with "great dislike" and calling him "an arrogant bullying toerag." After he asked her out in their fifth year, she replied that she wouldn't go out with him if it was a choice between him and the giant squid and remarked that, "I'm surprised your broomstick can get off the ground with that fat head on it. You make me SICK!" From this, Harry gathered the impression that Lily hated James, but Sirius and Lupin assured him that she didn't hate her future husband, they simply got off on the wrong foot. J. K. Rowling commented on Lily's hatred of James in an interview with The Leaky Cauldron/MuggleNet:

MA: How did they get together? She hated James, from what we've seen.

JKR: Did she really? You're a woman, you know what I'm saying.

After James matured and changed his attitude, Lily started dating him in their seventh year, eventually falling in love and marrying him, with Sirius as best man at their wedding.

Petunia recalls meeting an 'awful boy' who knew about magic, but it is not clear she meant James. Lupin told Harry that his parents only became attached in their seventh year, and married soon after leaving Hogwarts. It is not known what careers they took up after leaving school. Rowling has said in an interview that "James inherited plenty of money, so he didn't need a well-paid profession."

James, Lily, and Harry
James and Lily had a son, Harry James Potter, born on 31 July 1980. James and Lily belonged to the Order of the Phoenix, which was an organization created for wizards who wanted to battle Lord Voldemort and his followers, the Death Eaters. This organization was created and led by Albus Dumbledore. Dumbledore was given a prophecy by Sybill Trelawney that someone had been born who could defeat the Dark Lord to parents who had already defied him three times. Voldemort was told part of the prophecy by Severus Snape, who had been caught outside the door after the prophecy was heard. Athough both Harry and Neville Longbottom matched the description, Voldemort went after Harry, resolving to kill him. The Potters were deep in hiding through the Fidelius Charm, but on 31 October 1981, the Potters' whereabouts were betrayed by their friend Peter Pettigrew and they were attacked without warning at their home in Godric's Hollow. Their confrontation ended with first James and then Lily dead, and Voldemort himself barely alive. Whether there was anyone else present in Godric's Hollow on this night, Rowling has said, "No comment." Harry was taken in by Lily's sister, Petunia, who is married to Vernon Dursley. Their son and therefore Harry's cousin, Dudley Dursley, is a spoiled, gluttonous bully.

Lily could have saved herself when her family was attacked by Voldemort since he offered her the chance to step aside while he killed Harry. This was shown in a flashback sequence during Harry Potter and the Prisoner of Azkaban. Voldemort's motives for offering to spare Lily's life are unclear, but Lily refused and Voldemort killed her; the upshot of her selfless act was to invoke an ancient magic that gave Harry an innate defence against Voldemort (Rowling has stated that Lily did not know that this would happen because "it never happened before"). This magic manifested itself two ways: First, when Voldemort attempted to kill Harry with the Killing Curse, Avada Kedavra (which had never before been survived), the spell backfired, rendering Voldemort non-corporeal.

Voldemort's inability to touch Harry, due to his lingering protection, continued in Harry Potter and the Philosopher's Stone. Professor Quirrell, acting as host to Voldemort, attempted to attack Harry to gain the Philosopher's Stone, but was prevented from stealing the Stone when he came into contact with Harry's skin, leaving Voldemort forced to return to his non-corporeal state. Voldemort has since overcome this by using Harry's blood to regenerate his own body. However, when Harry tells Dumbledore this, he thinks he sees, for a fleeting instant, "something like triumph in Dumbledore's eyes." Harry thinks he must've imagined it though, for Dumbledore merely says "Very well, Voldemort has overcome that particular barrier." When asked about the gleam of triumph, J. K. Rowling says, "That's still enormously significant. And let's face it, I haven't told you that much is enormously significant, so you can let your imaginations run free there." 

The second way in which Harry is protected by Lily's sacrifice occurs at the Dursley residence in Little Whinging. Dumbledore admitted to Harry that he had extended Lily's protection to the home where Lily's sister Petunia lived. This was possible because Lily and Petunia are related by blood. As long as it continues to be Harry's home, Voldemort cannot harm Harry there. This protection at the Dursley's ends when Harry comes of age at 17.

James's Animagus form is a stag, like Harry's Patronus. James was therefore nicknamed "Prongs." Though Harry bears a great resemblance to his father, it is often noted that he has Lily's eyes. Rowling has said that, "Harry has his father and mother's good looks. But he has his mother's eyes and that's very important in a future book." Rowling has also said there will be more details appearing about Lily in the seventh and final Harry Potter book.

Family tree
James and his school friend Sirius Black may actually be first cousins once-removed. Rowling donated a copy of the Black family tree to a charity auction which shows a Charlus Potter married to Dorea Black, daughter of Cygnus Black and Violetta Bulstrode (maybe related to Millicent Bulstrode, Slytherin) and granddaughter of Phineas Nigellus Black. Some fans speculate that Dorea and Charlus may have been James's parents. In this case, James would have been a (much younger) first cousin of Walburga Black and her brothers. This would make Harry and Sirius second cousins. However, this contradicts Rowling's statements that James's parents were "old in wizarding terms" when they died, since she has also said that wizards have "a much longer life expectancy than Muggles". (Griselda Marchbanks is known to be over 160 and Albus Dumbledore about 150; Dorea died at only 57.) On the other hand, J.K. Rowling freely admits to being a poor mathematician, so it is entirely possible that she intended Dorea to have been older than she appeared on the tree.