Peter Quill wasn't always the wisecracking cosmic goofball brought to life by Chris Pratt in theaters everywhere. When first conceived and executed by Steve Englehart and Steve Gan, he was more of a jerky orphan who got hold of some mad cosmic skills. He initially donned a costume that looks like something of a cross between the intergalactic 5-0 and an un-caped crusader—which makes some sense, seeing as the Star-Lords was another form of cosmic cops.
Peter starts life rocking a mushroom-like army helmet and a uniform, complete with utility belt-looking thingy, which protects him to from the vacuum of space. It also allows him to fly, all while looking like a total fool. This incarnation of Pete also brought with it a rinky-dink version of the Element Gun, even if it was still capable of harnessing and controlling air, water, earth, and fire (but not heart) at will.
When writer Chris Claremont (of Uncanny X-Men fame) and artist John Byrne later took over, they ditched the mushroom-like helmet whenever possible, leaving Star-Lord with just a silly cowl. For his return in 2004, he got a major overhaul, and yet another update when he and Marvel Cosmic went to war with a bunch of power-hungry space bugs from the Negative Zone, during the "Annihilation" story line. At that point, his space uniform, complete with a nifty hypno-eyed space helmet, consistent with his more-recognizable look, began to take shape.
When adapting Star-Lord for the cinema, though, Marvel revamped his getup once again, giving Star-Lord more of a slacks, t-shirt, and a killer space ranger jacket affair—perfect for the casual space adventurer/son of a planet that he became.