Peter Quill was born in 1980 to Meredith Quill and an unnamed father. When Peter was young, his mother brought together some of her favorite songs from her childhood into a mix tape she titled "Awesome Mix Vol. 1". Quill grew up and lived in Missouri. Peter got into fights a lot as a kid. Over time, his mother had gotten terminal cancer. When Peter was at the age of eight, his mother's illness had gotten worse. Shortly before she died, she gave Peter a present and a note attached to it. In her final moments she begged Peter to hold her hand, but he couldn't bare to look at her. He regretted it and cried for his mother but was pulled out of the room by his grandfather.
Directly after her death, Peter ran out of the hospital crying. He was suddenly abducted from Earth by the Ravagers. Their mission was to take him to his father in deep space but their leader, Yondu Udonta, instead decided that they would keep him as their own and chose never to tell him about his father. The Ravagers taught Peter how to be the perfect thief. As he grew older, Peter started going by the name Star-Lord, which was a nickname given to him by his mother. Yondu gave Peter an M-ship that he named the Milano, after his childhood crush, Alyssa Milano.
Quill's extensive Nova Corps criminal record includes 1 count of fraud, 2 counts of public intoxication, 1 count of assault and 1 count of illegal manipulation of Garmosian Duchess.
After living in space for 26 years, Quill built up a reputation as the self-proclaimed legendary outlaw "Star-Lord" and worked for the pirate Yondu Udonta, the leader of the Ravagers. During his time with them, he became disloyal to them, eventually planning to leave them. In present day, Star-Lord visits Morag, where the Ravagers' next target, the Orb, was located. He is attacked by Korath the Pursuer but manages to escape. After escaping, Star-Lord travels to Xandar in order to sell it. He brings it to the buyer who had made the deal with Yondu in hopes of selling it. The merchant refuses to take the Orb after Star-Lord tells him that Korath had been working for Ronan the Accuser.
As he left the shop, Star-Lord encounters Gamora, an assassin, who, after he attempts to flirt with her, attacks and steals the Orb. Star-Lord is also attacked by the outlaw duo of Rocket Raccoon and Groot, who both desire the bounty that had been placed on Star-Lord's head by the Ravagers. After a lengthy chase, all four are eventually apprehended by the Nova Corps and taken to the Kyln for incarceration. After being processed, Star-Lord almost finfs himself a target in the prison, only to be saved by Rocket and Groot who declare that Quill was their booty. That night, some prisoners, including an inmate named Drax, come to kill Gamora.
Quill manages to convince Drax that, since she had betrayed Ronan, he would most likely come for her allowing Drax to exact his revenge. The next day, Rocket devises a plan to break out of the Kyln, which went awry when Groot completed the last step first. Nonetheless, the group manages to escape.
On the Milano, Gamora explains to the group that the third party to whom she was planning to give the Orb was offering a large reward for it, and that if they help her bring it to him, she would split the reward with them.
Arriving on Knowhere, a remote criminal outpost in space built in the giant severed-head of a celestial, the rest of the group meet Gamora's contact, the Collector. The Collector reveals that the Orb is an Infinity Stone, an item of immeasurable power that destroys all but the most powerful beings who wield it. Suddenly, the Collector's tormented assistant grabs the Stone, triggering an explosion that engulfs his collection. Meanwhile, Drax, drunk and wanting revenge, summons Ronan, who arrives with Nebula and an army of Sakaarans. Gamora attempts to flee with Orb only to be pursued by Nebula who blast her ship and retrieves the Orb leaving her sister to die in space. Star-Lord, unwilling to watch Gamora die, sends Yondu his coordinates and exits his pod giving Gamora his mask to help her survive. The pair are rescued by the Ravagers and Yondu who Quill manages to talk out of killing him by telling him he knows where there Orb is and that they can work together to retrieve it.
Suddenly Rocket, Drax, and Groot threaten to attack the Eclector in an attempt to rescue them, luckily Star-Lord manages to defuse the situation. On the ship Star-Lord tells the group that he has a plan to stop Ronan and tells the others that even though it likely means certain death they cannot simply stand back as Ronan kills billions of innocent people. The entire group agrees and so Star-Lord calls Rhomann Dey and tells them of his plan. Ronan arrives with the Dark Aster and thousands of Sakaaran soldiers.
As the Nova Corps hold off the large ship by creating a forcefield, Quill, Gamora, Groot, and Drax fight their way to Ronan and blast him with the Hadron Enforcer; however, Ronan is unaffected by the attack and easily defeats the group. Before he can kill them, Rocket comes crashing in with his own ship heavily damaging the ship and causing it to crash. The group is protected from serious injury by Groot who shields them seemingly at the cost of his life, making a dome around the team. As Ronan emerges from the ship unharmed, mocking the Guardians, Star-Lord distracts Ronan by dancing to "O-o-h Child" by the Five Stairsteps, allowing Drax and Rocket to destroy his hammer and allowing Star-Lord to grab the Orb, which almost kills him. Gamora, Rocket, and Drax come to his aid and the four use the Orb's power to blast Ronan, killing him.
After the team destroyed Ronan, Yondu demands that Star-Lord hand over the Orb despite Star-Lord telling him that it is only safe with the Nova Corps. Quill tricks Yondu into taking a container supposedly containing the stone but actually contained a Troll doll. As the Ravagers leave Xandar, they remarked that it turned out well that they did not deliver Star-Lord to his father as a child. After the Ravagers left, Star-Lord gave the real Stone to the Nova Corps. Star-Lord's group, now known as the Guardians of the Galaxy, have their criminal records expunged by the Corps, and Star-Lord learned that he is only half-human, his father being part of an ancient species. Star-Lord finally opened the last present he received from his mother; a second cassette tape filled with her favorite songs. The Guardians leave in the rebuilt Milano accompanied by a twig recovered from Groot, which has already started regrowing.
The Guardians came to Earth in search of Michael Korvac. The Avengers engaged in battle with the Guardians and Hawkeye took to fighting Star-Lord. They made their way to the kitchen and Star-Lord convinced Hawkeye to listen to what he has to say. The Guardians and Avengers formed an alliance but were sucked into the Soul Gem. When they were out, they worked together to take down Michael Korvac. But the cosmic-powered madman had defeated them. Witnessing Korvac's shaking feelings from the words of Corrina, the Avengers and the Guardians were surprised. As the Guardians prepared to leave, Iron Man wanted to know what other threats of the universe, but Star-Lord had grimly replied that it's better not knowing about it at all.
The Guardians battle the Chitauri an alien race led by Korvac. When Rocket Raccoon's ship is pulled into the Chitauri ship, Rocket fakes surrender so that they can free the captive Guardians of the Galaxy members. Afterwards, Spider-Man discovers that the Chitauri are planning to destroy the Earth. The Guardians plan to run the Chitauri ship into the sun while fighting the Chitauri forces. When their tactic does not work, the Guardians end up making their way towards the Dark Matter Cannon. While Nova and Spider-Man head to the Dark Matter Cannon, the Guardians fight the Chitauri and Korvac. After Korvac is defeated by Groot, Nova destroys the Dark Matter Cannon and the Chitauri ship is destroyed, saving Earth.
In "The Return of the Guardians of the Galaxy", Star-Lord is with the Guardians of the Galaxy when they land on Earth to rebuild their ship at the same time when Titus was leading the Chitauri into targeting Nova's helmet.
After the Avengers and Guardians stop fighting, the Guardians explain that they took an artifact called the Kree Mact to avert it from falling in Ronan the Accuser's clutches. Both heroic teams face Fin Fang Foom and Ronan, and after the battle, the Guardians leave the Kree Mact under the Avengers' care.