Timeline

This is a timeline of canon events in the Adventure Time series.

Distant past

 * According to the Lich, before the universe existed, "there were monsters". The Lich, GOLB, and Hunson Abadeer existed as far as back then.
 * Millennia ago, Orgalorg the warlord was banished by Grob Gob Glob Grod to Earth for attempting to intercept a yellow Catalyst Comet to gain its power. He is transformed into a penguin.
 * On Earth during the Cretaceous period, four Elementals—Urgence Evergreen, Chatsberry, Balthus, and Slimy D—attempt to stop a green Catalyst Comet (the Lich) from hitting Earth, but fail and are killed by the comet. The Ice Crown is created during their attempt.

Up to the Mushroom War

 * Human civilization takes over the Earth.
 * What is now the Land of Ooo (or a part of it) was the "Wut-Wut State", as shown on a food truck's registration plate.
 * Simon Petrikov is born.
 * Simon discovers a crown in Scandinavia, and is influenced by its powers.
 * Patience St. Pim sees a future vision of the Mushroom War and freezes herself to survive.
 * 996 years before the present day - the Mushroom War takes place. The Mushroom Bomb kills most humans on the Earth and mutates many lifeforms. It also causes a major climate change.

Post-Mushroom War to the near present day

 * Simon Petrikov adopts a half-demon girl, Marceline, and raises her in the new post-apocalyptic world.
 * Two Bread Tom leads a tribe of surviving humans into a freighter. Marceline grows up to be a vampire hunter and protects him and his tribe. Tom and his group of humans settle on an archipelago at the southwest of the surviving continent of Ooo and build its Guardian.
 * Still other humans were not so fortunate—they were hunted down, killed, and eaten by vampires, oozers, and rainicorns.
 * A blue Catalyst Comet hits Earth. It is later reborn as a butterfly and a pink lump with a gold outline (a "thing").
 * 800 years before the present day - Princess Bubblegum and Neddy are born. They drop from the Mother Gum and create the Candy Kingdom.
 * 800 years before the present day - Princess Bubblegum creates Uncle Gumbald, Aunt Lolly, and Cousin Chicle as she felt lonely. The trio later tried to seize her from power and create a Dum Dum Juice to make her more docile and simple-minded. The act fails and the trio all become candy people, forgetting their previous identites, leading Bubblegum to the creation of the Candy Kingdom.
 * 300+ years before the present day - Shoko and her tiger go on adventures.
 * 200+ years before the present day - Magic Man's wife, Margles is abducted by GOLB. Magic Man later magically creates a defense device appearing as Margles to protect Mars from GOLB. Magic Man hiked to Olympus Mons with the Margles device, but of course had feeling for it as she resembled his lost wife. She then turns into a defense system, and Magic Man tries to stop the defense system realizing it was made from his nightmares. This led to Magic Man becoming "a jerk."
 * 200+ years before the present day - Magic Man is banished from Mars by the King of Mars and Grob Gob Glob Grod and sent to Earth/Ooo.
 * Some time before the present day - Billy casts the Lich down, imprisoning him in amber in the heart of the tree in the middle of the Candy Kingdom.
 * Some time before the present day - Princess Bubblegum creates the Earl of Lemongrab
 * Some time before the present day - Warren Ampersand comes to the Land of Ooo, to pass on his stretchy powers into a compatible breeding partner. Warren finds Joshua the Dog, and infects/impregnates him, leading to the birth of Jake.
 * 17 years before the present day - Finn Mertens is born on Hub Island to Martin Mertens and Minerva Campbell.
 * Around 17 years before the present day - Martin escapes his home islands with his baby son Finn and evades its Guardian. He leaves Finn behind on the raft and he drifts to Ooo, where he is eventually found/adopted and raised by Joshua and Margaret.
 * Finn and Jake's parents, Joshua and Margaret, pass away of unknown causes.
 * Lady Rainicorn leaves the Crystal Dimension, breaking up with her boyfriend Lee and moves to the Land of Ooo.
 * Jake was a criminal in a gang with Tiffany Oiler, the Flying Lettuce Brothers, and Gareth. He also was Card Wars groups and had a girlfriend named Moniker, whom he eventually broke up with.

Present day

 * Finn and Jake go all across the Land of Ooo, helping others, going on quests, destroying evil, making new friends, and much more.
 * Princess Bubblegum rules the Candy Kingdom, and works hard and goes anywhere to protect the candy citizens. She is often assisted by Finn, Jake, and other people.
 * The Ice King occasionally attempts to kidnap various princesses, but is thwarted by Finn and Jake.
 * Finn and Jake go to Mount Cragdor and obtain the Enchiridion.
 * Finn and Jake go on an adventure with Tree Trunks to find the Crystal Gem Apple. After finding it, Tree Trunks bites it, and suddenly disappears and is transported to the Crystal Dimension.
 * Finn and Jake meet Marceline.
 * Finn and Jake meet Magic Man.
 * Finn and Jake meet Billy.
 * Finn summons Marceline's dad Hunson Abadeer to Ooo from the Nightosphere.
 * Finn and Jake are transported to the Crystal Dimension, only to find Tree Trunks now the Crystal Queen. She has gone mad since becoming ruler, but Finn and Jake remove the Crystal Gem Apple from her, reverting her back to her old self and returning home.
 * Finn and Jake meet Susan Strong.
 * The Lich is accidentally released from the amber prison. Supposedly defeated, the Lich still lives on, possessing the Snail.
 * Lemongrab comes to Candy Kingdom claiming reign due to Princess Bubblegum's temporary youth.
 * The Ice King writes about Fionna and Cake.
 * Finn and Jake find out about Ice King's origin and begin to pity him more.
 * Finn and Jake meet Flame Princess, who later becomes Finn's girlfriend.
 * Lemongrab 2 to live with Lemongrab in Castle Lemongrab.
 * Finn gives away the Enchiridion to a Bear, who unbeknownst to him, is working for the Lich-possessed snail.
 * Grob Gob Glob Grod comes to Earth looking for Magic Man, planning to put him on trial for his past offenses on Mars.
 * Lady Rainicorn announcing her pregnancy.
 * The Lich leaves the snail and possesses and kills Billy. The Lich uses Finn's trust with Billy, to lure him into using the Enchiridion to create a portal to the multiverse, in which he can wish for the extinction of all life. However, Finn and Jake stop the attempt. Finn and Jake meet Prismo in this time, and Finn's wish leads to the creation of the Farmworld timeline.
 * Jake and Lady's five children are born.
 * Castle Lemongrab has gone through major changes, now inhabited with Lemon People, one them being Lemonhope, who later leaves, but returns freeing the Lemon people
 * Ice King stops kidnapping princesses.
 * Finn and Flame Princess break up.
 * Finn gets the Grass Sword.
 * The Ice King's curse is temporarily broken and he is reverted back to Simon. He creates a time portal and accidentally brings his former fiance Betty to the future. Simon is shorty reverted back to the Ice King, but Betty vows to find a cure.
 * Finn finds out about biological father Martin, and goes with Jake to the Citadel to meet him. In this time, The Lich is (mostly) destroyed and becomes a giant baby known as Sweet P, after being covered with the citadel guardian blood. Martin does not care for Finn, and climbs up a giant stem with alien creatures to leave with, Finn then grabs the two halves of the severed stem tighter and preventing his father from leaving, telling he won't let him escape and he struggles to hold on. The Grass Sword then takes over Finn's right arm, allowing him one last tremendous pull. Martin grosses out at this and asks the void caster to enlarge the void. This causes much pressure on Finn's hand and at last, Finn's arm gives out and is severed from his body.
 * Breezy brings Finn's arm back. The arm is later revealed to actually be prostetic, and made from grass, as residue of the Grass Sword.
 * Finn gets the Finn Sword.
 * Martin pilots a spaceship and is about to crash into Mars, but Grob Gob Glob Grod diverts it (and is killed) towards Earth, mistaking it for another blue Catalyst Comet.
 * By mistake, Magic Man looses his magic powers along with his insanity, and they are transferred to Betty.
 * The Candy Kingdom as its very first election. Princess Bubblegum is outvoted and her opponent, the King of Ooo becomes the new ruler of the Candy Kingdom.
 * Orgalorg emerges from Gunter and attempts to swallow the current purple Catalyst Comet to gain its powers, but is defeated. Martin accepts its offer and disappears from the universe.
 * Princess Bubblegum cures Marceline's vampirism, but in the process, accidentally revives the five vampires she gained her powers and vamprism from. In the end the vampires are defeated and Marceline becomes a vampire once more.
 * The Candy Kingdom overthrows the King of Ooo and give the throne back to Princess Bubblegum
 * Prismo sends Finn and Jake to the Farmworld to stop the Farmworld Ice Finn and the Farmworld Lich/Jake from created a portal the universe with their timeline's Enchiridion. Finn and Jake cure both of their counterparts, and Finn secretly takes the Enchiridon back with.
 * Magic Man turned Normal Man, leaves Earth and returns to Mars, taking the place of Grob Gob Glob Grod and Abraham Lincoln as King of Mars.
 * Patience St. Pim emerges from her 1000 year hyper-sleep, as she froze herself to survive the mushroom war. She is obsessed on unleashing the full magical potential of herself and the other elementals.
 * The Finn Sword, and Finn's grass sword/arm, merge into a being, which is later known as Fern. Due to grass sword leaving Finn, he is amputated once more.
 * Finn, Jake and Susan Strong leave Ooo to visit the islands, in which they find out the fate of the humans.
 * Finn and Jake come home from the islands, only find out that Patience St. Pim had set up a mega-elemental spell, in which all of Ooo was transformed/possessed by the elements. The act is countered by the anti-elemental lumps of Lumpy Space Princess, reverting everyone back to their "true shape." At this same time Betty had kidnapped Ice King using the new farmworld Enchiridion to change time and prevent Simon from wearing the Ice Crown. However, Ice King interferes and Betty is teleported to Mars.
 * Due to the anti-element lumps of Lumpy Space Princess, Gumbald, Lolly, and Chicle are reverted back to their original selves and immediately resume action on destroying Princess Bubblegum.
 * The hand of the Lich-possessed Farmworld Jake, had jumped into the multiverse portal. The hand has the consciousness of the Lich and is taunted Sweet P, wanting the two to reign. Sweet P however does not approve of this and destroys the hand.
 * Due to time slips set off by Clock Bear, Jake sees his own birth. Not much later, he is abducted by Warren Ampersand and taken to his supposed homeworld. Jake finds out the source of his stretchy powers and Warren's motive, which was to kill him and steal his powers. Jake not liking this throws his father into a black hole, but leaving him stranded on the planet.
 * Finn and Jermaine travel to Mars to seek guidence from Normal Man turned King Man, looking for Jake. They come across Betty and the three enter a Mars temple to undergo mind challenges. Betty was supposed to be cured of her obsession with curing the Ice King, but instead comes up with a plan to save Simon and King Man's wife Margles from GOLB. In the process Jake is retrieved and goes home with Finn.
 * Gumbald forms a powerful city-state called Gumbaldia.
 * The Candy Kingdom and Gumbaldia declare war on each other beginning the Gum War.

Future events

 * 1000 years after the present day - Finn and Jake's tree fort extends high up into the sky; the Candy Kingdom is now an abandoned metropolis and is guarded by the Prize Ball Guardian who stores its inhabitants inside its body; Marceline scavenges the remains of the Tree Fort and uses them in her house; the Ice Kingdom is inhabited by an enormous monster.
 * 1000 years after the present day - An alien, Cuber, recounts the tales of the past through his Graybles. Later, he uses the Graybles to navigate across the ruined Earth.
 * 1000 years after the present day - Lemonhope wanders through ruins of Ooo and the Candy Kingdom, and sleeps in his untouched bedroom in Castle Lemongrab after his adventures.

Farmworld Timeline

 * The world was created when Finn and Jake followed the Lich to the Time Room, where Prismo grants wishes. The Lich wished for "the extinction of all life." Finn attempted a counterwish, wishing that the Lich never existed, resulting in the creation of the Farmworld. Jake wished for he and Finn to return home, stopping the Lich wish, but despite this, the Farmworld continued to exist.
 * Simon Petrikov uses the powers of his Ice Crown to stop the Mushroom Bomb from detonating, and he dies as he gets crushed by the bomb's weight. The crown near Simon's corpse kept the bomb frozen for next 1000 years
 * The enraged Ice Crown unleashes an ice age upon the Earth, but humanity thrives in a less advanced state for 600 years.
 * Farmworld Finn discovers the Ice Crown, and becomes the new host of crown.
 * Farmworld Finn's ice powers sets off the Mushroom bomb, Farmworld Jake falls in the radioactive waste and becomes infected with the spirit of the Lich
 * Ice Finn and Lich Jake use the Enchiridion to create a portal to the multiverse. Lich Jake lied to Ice Finn, saying they will save the world.
 * Prismo sends in the standard timeline's Finn and Jake. Finn and Jake then cure both Farmworld Finn and Jake from the Ice Crown and the Lich and they are reunited with their family

Puhoy/Pillow World Timeline

 * Finn stays in Pillow World. He marries Roselinen and they have two children, Jay and Bonnie.
 * Archaeologists discover a door leading back to Ooo, but it lasts for a short time and suddenly disappears.
 * Finn grows old and dies. He comes face to face with GOLB, only to be returned back to his old life where he left off.