Rocket Raccoon first appears in Marvel Preview #7 (Summer of 1976).
Rocket Raccoon acts as the "Guardian of the Keystone Quadrant", an area of outer space sealed off from the rest of the cosmos by the so-called Galacian Wall. Rocket is captain of the starship Rack 'n' Ruin, and he and his first mate Wal Russ (a talking walrus) come from the planet Halfworld in the Keystone Quadrant, an abandoned colony for the mentally ill where the animal companions were genetically manipulated to grant them human level intelligence and bipedal body construction for many to become caretakers of the inmates. Rocket was Halfworld's chief law officer ("ranger") who protected the colony against various threats.
At one point, Judson Jakes tried to steal the Halfworld Bible, but was thwarted by Rocket and the Hulk. Later, Lord Dyvyne abducted Rocket's friend Lylla, and Jakes began the Toy War. As the Toy War continued, Blackjack O'Hare teamed up with Rocket, and Rocket was reunited with Lylla. The Rack 'n' Ruin was soon destroyed, as Judson Jakes and Lord Dyvyne teamed up to kill Rocket Raccoon. Rocket Raccoon and his friends cured the Loonies of their mental illnesses, as Judson Jakes and Lord Dyvyne were apparently killed. Rocket and the animals as well as the robots left Halfworld and took off into space for their own adventures. Some time later, Rocket was revealed to have been a laboratory subject on the Stranger's planet, and escaped his captivity there.
Rocket Raccoon resurfaced as a member of the team chosen to accompany Star-Lord on his mission to stop a Phalanx infiltration of the Kree homeworld. Rocket is depicted as a gifted military tactician who is also fearless, loyal, and insightful. It is also heavily implied that he has a case of obsessive compulsive disorder. Rocket's trademark rocket skates are absent.
Rocket Raccoon will appear in the live-action film Guardians of the Galaxy on August 1, 2014, with his voice provided by Bradley Cooper.