James Potter was born c. 1960 in England. He was described as having Hazel eyes, a slightly longer nose than Harry's, but otherwise the same thin face, same hands, same hair sticking up at the back, and being nearly the same height as Harry. He attended Hogwarts School of Witchcraft and Wizardry c. 1971 to c. 1978 where his best friends were Sirius Black, Remus Lupin, and Peter Pettigrew. Sirius fell out with his own parents and instead came to live with James' family from the age of 16. They treated Sirius as a 'second son', suggesting that James had no other brothers.
Described by Severus Snape as 'exceedingly arrogant', by Remus as 'the height of cool' and by Sirius as sometimes an 'arrogant little berk', he eventually matured by the end of his schooldays. Scenes from James' time at Hogwarts have shown him behaving as something of a bully towards Severus Snape, who was in the same school year. He had the habit of hexing anyone who annoyed him and was more skilled at magical duelling than Snape, despite Snape's recognised ability with dark spells. After seeing Snape's recorded memories of James, Harry agreed with Snape's assessment of his father's arrogance.
James was a brilliant student and was Quidditch Chaser on the Gryffindor house team. There is considerable confusion over whether James Potter was a Seeker or a Chaser. Rowling has confirmed that James was a Chaser, and that his being a Seeker was introduced in the Harry Potter films. Despite having been a Chaser, however, he was known to play 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 an action-man image
While at Hogwarts he met his future wife Lily Evans, who was also in his year. Lily's parents were said to be delighted to discover their daughter was a witch, but her sister Petunia was not. Lily was also a talented student, described by Professor Slughorn as having outstanding natural ability at potions, being cheeky, but always seeing the good in others. Also very brave, very funny, and that he could not imagine anyone meeting her would not have liked her. She became a member of the Slug Club, which was run by Slughorn for promising students. Some speculate that she may have been better at potions than Snape, and may have helped him in that subject.
James and Lily were Head Boy and Head Girl when they were in their final year. For most of the time they were at Hogwarts, Lily regarded James as an arrogant fool but when he matured she changed her mind and fell in love with him. James was shown doodling Lily's initials during an examination in their fifth year, while Sirius recalled that he always tried to show off whenever she was around. However, Lily defended Snape against his bullying and expressed contempt for his behaviour, showing 'great dislike' for him. They adressed each other only by surname, when everyone else was using nicknames. Petunia recalls meeting an 'awful boy' who knew about magic, but it is not clear she meant James, who she normally refers to by name. Remus told Harry his parents only became attached in their seventh year, and married soon after leaving Hogwarts. J.K. Rowling has said in an interview that "James inherited plenty of money, so he didn't need a well paid profession." It is not known what careers they took up after leaving school.