…well, in the movies at least.
Part of the mystery of Guardians of the Galaxy is that we don’t know who Peter “Star-lord” Quill’s dad is. Now, comics readers had a pretty good clue since it’s well established canon in Marvel’s main continuity… but that knowledge is apparently inapplicable for the Cinematic Universe. Director James Gunn, while talking with Empire said:
“There have been a lot of documents passed around about who Peter Quill’s father is between a select two or three of us,” says Gunn. “That’s been part of the plan since the beginning, that’s something I had to work out before we shot the screenplay. We wanted to make sure Yondu’s place in everything made sense and it does, so it’s all very specific stuff.”
Importantly, Gunn had a major revelation for fans trying to work out who Peter Quill’s father might be. “It’s definitely not the character who it is in the comics, I’ll say that much.”
So… yeah. Quill’s father won’t be J’Son, Emperor of the Spartoi Empire, in the movies.