A timeline/summary of the KH series. This will contain spoilers, but hopefully it'll help if you haven't played all the games/want a quick overview. If any clarification is needed, feel free to poke me and I'll explain in more detail. Also Zia is my lovely assistant.
Will be editing/adding things constantly.
Notes
+ Everything is depressing.
+ The only known Keyblade Masters are Xehanort, Eraqus, Aqua, Mickey, and Yen Sid.
+ Xehanort was born on Destiny Islands. First known person to leave. His Heartless/Xemnas both look like him when he was younger with hair etc. Kinda creepy when you include Terra factor.
+ The three different enemy types throughout the whole series are the Unversed, Heartless, and Nobodies.
+ go to bed Francy it's almost 6 am you can work on this later god you deserve to get caught by your parents
+ seriously stop getting out of bed to add things I hate you I don't care if I am you
• The Beginning
+ Is not a game. Discussed in BBS and KH1.
+ A story that Kairi's grandma told her when she was young. It describes the beginning of the fight between darkness and light.
+ In the beginning, there was only one world and light. The people eventually began to fight over the light, and their greed caused darkness to form. It covered everything.
+ The darkness is what broke the world apart, and is why there are now many different ones.
+ The true light became lost, although it remains hidden inside the hearts of children.
⊳ Worlds: The original one.
• Keyblade War
+ Is not a game. Discussed in BBS.
+ A war where countless Keyblade wielders died fighting over the ultimate Keyblade: The χ-blade.
+ It seems like there were hundreds, if not thousands, of people who wielded the Keyblade at one time. How many that are actually left is unknown. At least by the events of BBS, it's implied that there are more out there.
+ Area where it occurred is known as the Keyblade Graveyard.
+ The war occurred when everything was still covered by darkness. Apparently. We need actual dates, Nomura.
⊳ Worlds: Keyblade Graveyard.
• Birth By Sleep
+ Occurs ten years before the events of KH1.
+ Ventus, whose heart was splintered, is dumped on Destiny Islands by Xehanort. His heart comes in contact with Sora's, who heals him through his magical Sora powers. It makes sense. Ven's heart only contains light because his darkness manifested itself into another form known as Vanitas. Occurs four years before the main story.
+ Xehanort wishes to forge the χ-blade by using Ven in order to create another Keyblade War. He also wishes to get a younger body. Hi Terra.
+ Ven, Aqua, and Terra are the students of Eraqus in the Land of Departure. Terra and Aqua undergo the Mark of Mastery exam to become Masters. Only Aqua passes.
+ Xehanort disappears. Eraqus sends Terra to investigate, and sends Aqua to keep an eye out on Terra. Ven meets Vanitas, and chases after Terra.
+ They all travel across various worlds, occasionally crossing paths, but for the most part their journeys are different.
+ Maleficent begins her plot of capturing the Princesses of Heart.
+ Mickey is training under Yen Sid to become a Keyblade Master.
+ Riku and Kairi both go through the Keyblade Inheritance Ceremony (intentionally and accidentally). Because of this, they're able to wield the Keyblade when they're older. Sora, however, did not go through it which is one of the reasons why he's special.
+ Braig has been working with Xehanort this whole time.
+ Ven finds out his true purpose as the χ-blade.
+ The enemy "monsters" are the Unversed, which come from Vanitas.
+ Terra and Eraqus fight over Ven, and Xehanort kills Eraqus.
+ Meeting at the Graveyard. While the plan to make an χ-blade fails (Ven loses his heart in the process, although it seeks refuge within Sora's), Xehanort does gain Terra's body. Which is why he looks younger in the following games. Land of Departure is transformed into Castle Oblivion, and Aqua hides Ven's body there. In the final battle, Aqua confronts Terranort, and they both all into the Realm of Darkness. While Aqua is able to save Terranort, she is trapped in it, and has been traveling inside it for the last ten years.
+ Terranort becomes an apprentice of Ansem in Radiant Garden. He has amnesia.
⊳ Worlds: 100 Acre Wood, Castle of Dreams, Deep Space, Destiny Islands, Disney Town, Dive to the Heart, Dwarf Woodlands, Enchanted Dominion, Keyblade Graveyard, Land of Departure/Castle Oblivion, Mirage Arena, Mysterious Tower, Neverland, Olympus Coliseum, Radiant Garden, and Realm of Darkness.
• Birth By Sleep volume two
+ Has not been officially confirmed as a game, but BBS Final Mix's secret ending heavily implies that it will be.
+ Shows Aqua witnessing the destruction caused after the apprentices unlock the heart and turn themselves into Nobodies (Isa and Lea get caught in it as well). This happens nine years before KH1, so this means that volume two might be one year after BBS.
+ Shows Cinderella's world engulfed by the darkness.
+ Kairi was sent to Destiny Islands around this time. Radiant Garden!FF characters flee to Traverse Town.
+ It is implied that this game(?) will span throughout the entire KH series up until KH3. Nomura has stated in the past that he wanted to do a game that explored what Mickey and Riku did in the Realm of Darkness, so this will most likely be the same game. Only it also has Aqua.
+ No other information has been revealed.
⊳ Worlds: Realm of Darkness.
• Kingdom Hearts
+ Sora, Riku, and Kairi are building a raft to explore other worlds. The idea was influenced by Kairi coming from another world, as well as Xehanort leaving the Islands years prior and Terra confirming that it's possible.
+ Riku opens the Door that unleashes darkness upon the world. Kairi loses her heart and vanishes. Riku disappears into the darkness. Sora gains the Keyblade, also disappears, and arrives in Traverse Town.
+ Mickey leaves Disney Castle to explore the disappearance of worlds. He sends Donald and Goofy on a quest to find the Keyblade. They meet with Sora in Traverse and journey together.
+ Maleficent continues her quest to collect the Princess of Heart in order to create the Door to Darkness. She convinces Riku to join her by making him believe Sora replaced him.
+ Riku finds Kairi, and reveals to Sora that she lost her heart. She remains in a comatose state.
+ Maleficent collects all of the Princesses. All of them.
+ Eventually Sora, Donald and Goofy reach Hollow Bastion which was previously Radiant Garden. Riku reveals that he was the real Keyblade wielder, and that Sora was simply bringing the weapon to him. He takes the Keyblade, which forces Donald and Goofy to go with him.
+ Donald and Goofy go back to Sora, and then the Keyblade returns to him. Riku runs, and his heart completely succumbs to darkness. Xehanort's Heartless possesses him.
+ It is revealed that Kairi is the final Princess, and that her heart is inside Sora's. In order to free it, Sora stabs himself which unleashes both of their hearts. Her heart is returned, which in turn opens the Door, and Sora turns into a Heartless. He gets better.
+ This act creates both Roxas and Naminé, their Nobodies.
+ Kairi gives him her good luck charm.
+ Sora, Donald, and Goofy go through the Door which takes them to The End of the World. There, they encounter Rikunort and defeat him in battle. Rikunort tries to open Kingdom Hearts, but apparently it was the Door to Light and he gets blinded and dies. I guess. And then it turns out it leads to the Realm of Darkness. I guess. In order to fully close it, Riku and Mickey stay on the other side.
+ Sora restores all the destroyed worlds. Kairi returns to Destiny Islands. Sora, Donald, and Goofy begin a new journey to find Riku and Mickey.
+ This features the first appearance of the cloaked figures in the secret endings/Final Mix.
⊳ Worlds: 100 Acre Wood, Agrabah, Atlantica, Deep Jungle, Destiny Islands, Disney Castle, Dive to the Heart, End of the World, Halloween Town, Hollow Bastion, Monstro, Neverland, Olympus Coliseum, Traverse Town, and Wonderland.
• Chain of Memories
+ Begins immediately after the events of KH1. Its duration is about a month. Seriously.
+ The official introduction of the Organization. Sora meets Axel, Marluxia, Larxene, and Vexen.
+ Marluxia and Larxene are planning on taking over the Organization. Axel's official mission is to find the traitors and dispose of them.
+ Sora, Donald, and Goofy encounter a hooded figure (Marluxia) that leads them to Castle Oblivion. He warns them that inside, they will lose their memories while recovering new ones. Only in a more cryptic and vague manner.
+ All the "worlds" are places that Sora visited. They're all figments of his memory, and none of his friends remember who he is.
+ Sora begins to "remember" Naminé, while forgetting all of his other friends and the worlds he visited. He learns that the Organization is holding her captive in C.O.
+ "Riku" appears, acting much like how he did when he was on Maleficent's side. He and Sora share the same exact memories concerning Naminé.
+ Vexen decides to tell Sora about Roxas. Axel kills Vexen in order to gain Marluxia and Larxene's trust. Sora is not pleased.
+ Sora, Donald, and Goofy split up.
+ Axel lets Naminé go. Cause he can.
+ It's revealed that Naminé was manipulating the memories of Sora, Donald, Goofy, and "Riku". It's also revealed that "Riku" was actually a replica that I will call Repliku from now on. Naminé crushes Repliku's heart, and Sora defeats Larxene. Donald and Goofy rejoin him.
+ Sora heads off to defeat Marluxia. Marluxia kidnapped Naminé, and he and Axel are fighting. Marluxia escapes, and Axel confesses that he has no interest in getting in Sora's way. Sora goes after Marluxia again, and gets help from Repliku. Sora then defeats Marluxia.
+ Repliku disappears. He later runs into Axel.
+ Naminé reveals that she did so much damage to their memories that the only way to fully reconstruct them would be to put them to sleep and for them to forget the events of CoM. The three of them agree, Sora promises her that they'll meet again, and she begins to work.
⊳ Worlds: 100 Acre Wood, Agrabah, Atlantica, Castle Oblivion, Destiny Islands, Halloween Town, Hollow bastion, Monstro, Neverland, Olympus Coliseum, Traverse Town, Twilight Town, and Wonderland.
• Reverse/Rebirth
+ A part of CoM, but it's Riku's side of the story.
+ Riku meets Vexen, Zexion, and Lexaeus.
+ Riku arrives at C.O. after Sora's heart led him there. He is lonely.
+ Unlike Sora, the worlds that Riku visits are completely empty besides bad guys. Again, forever alone. Xehanort's Heartless shows up, but so does Mickey. It's not really Mickey though, more like a projection because he can't get there yet.
+ Riku can "smell" darkness. Zexion shares this ability.
+ Vexen confronts Riku, fights him, and uses the data he collected from the fight to create Repliku. Repliku fights him and loses.
+ Riku travels through C.O. and during this time both Vexen and Larxene are defeated.
+ Riku and Lexaeus fight. Xehanort's Heartless takes control of Riku, and kills Lexaeus. Mickey saves Riku from being completely consumed by the darkness.
+ Sora defeats Marluxia. Zexion appears before Riku and tries to manipulate him. He almost succeeds, but Naminé comes to Riku's rescue. Riku defeats Zexion, but he gets away.
+ Axel and Repliku kill Zexion. He apparently knew too much.
+ Riku reunites with Mickey, and it turns out that Xehanort's Heartless was really Ansem/DiZ. Riku goes to find Naminé but encounters Repliku. They have one more battle, and Repliku finally dies.
+ Naminé gives Riku the choice of going to sleep in order to seal away the darkness in his heart, although it would erase his memories of the whole adventure. He chooses to keep his memories. He joins DiZ, as well as Naminé, in order to restore Sora's memories.
⊳ Worlds: Agrabah, Atlantica, Castle Oblivion, Destiny Islands, Halloween Town, Hollow bastion, Monstro, Neverland, Olympus Coliseum, Traverse Town, Twilight Town, and Wonderland.
• 358/2 Days
+ Begins at the very end of KH1, goes throughout CoM, and ends where KH2 begins.
+ Tells the story of Roxas and the Organization.
+ The Organization collects hearts in order to create Kingdom Hearts, which will give them their hearts back.
+ Xemnas finds him in Twilight Town. Roxas is put into the care of Axel.
+ Xion joins a week after Roxas.
+ Roxas and Axel become friends, but Axel is soon sent to C.O. with the others. In Axel's absence, Roxas becomes friends with Xion.
+ Roxas falls into a coma at the same time Naminé puts Sora to sleep. He wakes up sometime but afterward starts to experience Sora's memories. He starts to question his role and the Organization.
+ Axel returns as the only survivor of C.O. He's initially wary of Xion, but the three of them become bff.
+ It's revealed that Axel and Saïx have been secretly working together to take control of the Organization. They are beginning to drift apart and they eventually cut ties.
+ It's revealed that Xemnas is searching for a room in C.O. Specifically the one Ven is sleeping in.
+ Riku has been stalking the Organization in his coat. They've noticed.
+ Xion runs into Riku, who calls her a fake. She eventually runs into Riku again, and he reveals to her that she's really a replica of Sora. She looks like Kairi because the memories of her are Sora's strongest. She joins him, and learns from Naminé that the only way for Sora to wake up is for she and Roxas to rejoin him.
+ Axel brings Xion back by force. Xemnas then reprograms her to fight Roxas and absorb him.
+ Roxas leaves the Organization. Axel is forever alone.
+ Roxas and Xion fight. It turns out that Xion was faking becoming evil, and she wanted Roxas to defeat her. She dies in his arms after telling him to stop Xemnas. Everyone completely forgets about her due to her existence as a memory-based replica.
+ Roxas goes to defeat the Organization, but is intercepted by Riku. They fight, and Riku uses the darkness in his heart to defeat him. Doing this changes his form to look like Xehanort's. He, Naminé, and DiZ place Roxas in a simulated Twilight Town to hide him from the Organization until Naminé completely restores Sora's memories.
⊳ Worlds: Agrabah, Beast's Castle, Castle Oblivion, Destiny Islands, Halloween Town, Neverland, Olympus Coliseum, Simulated Twilight Town, The World That Never Was, Twilight Town, and Wonderland.
• Kingdom Hearts II
+ A year after the events of KH1.
+ Roxas is living in the simulation. His memory has been replaced with a false one, and his personality is slightly altered. He's "friends" with Hayner, Pence, and Olette who are residents of Twilight Town, and they are enjoying their vacation.
+ Axel is given the job of bringing Roxas back to the Organization. For some odd and confusing reason, Roxas does not trust the strange man in the black coat.
+ It is revealed that DiZ is racist against Nobodies because his apprentices (the original six members of the Organization) betrayed him.
+ Roxas eventually learns that he's Sora's Nobody from Naminé. He goes to confront DiZ, defeats Axel, and finally comes face to face with a sleeping Sora. He rejoins Sora, and his summer vacation ends. DiZ tells Rikunort to kill Naminé. He finds her with Axel, and instead lets them go free. They run away together.
+ It turns out that everyone had forgotten who Sora was while his memories were being reconstructed. Kairi, although she barely remembered him, sent him a letter. Everyone suddenly remembers him again once the restoration is complete.
+ Sora, Donald, Goofy, and Jiminy (oh right, he's there too) all wake up. They discover that they have no idea how they got there, all their records of their previous adventure had been erased except for one line: Thank Naminé. Obviously they have no idea who the hell she is.
+ They encounter Mickey, who tells them to go to Yen Sid. Yen Sid informs them of Nobodies. They begin their journey of finding Riku and defeating the rest of the Organization.
+ They go to various worlds and encounter the surviving members of the organization: Demyx, Xigbar, Xaldin, Luxord, Saïx, and Xemnas. Axel is no longer a part of it. They defeat them one at a time.
+ Axel kidnaps Kairi because that will bring Roxas back. It's a great plan. Saïx kidnap-kidnaps her.
+ It is revealed that while Xemnas may not remember everything, he does remember that Aqua and Ven are his friends. Terra's memories are bleeding through.
+ Sora finds out from the Twilight Town gang that Kairi was kidnapped. He heads off to The World That Never Was to save her. Axel sacrifices himself in order to help Sora, and tells him to say sorry to Kairi for him. Sora never does.
+ Sora has another Dive to the Heart where he fights Roxas, and where Roxas finally accepts that it has to be Sora and not him.
+ Naminé rescues Kairi. They run into Saïx, but Rikunort arrives. Saïx and Naminé both leave, and Rikunort gives Kairi a Keyblade. That he was just holding onto.
+ Sora runs into the two of them. He has a cute reunion with Kairi, an adorable OT3 moment, and then goes all out gay for Rikunort. They run into Mickey.
+ DiZ tries to digitize Kingdom Hearts with a machine. It blows up on him and sends him to the Realm of Darkness where he eventually meets Aqua. That was also a good idea. This does give Riku his normal body back however. Thanks, DiZ!
+ Sora, Donald, Goofy, Riku, Mickey, and Kairi all go to defeat the Organization. They "defeat" Xemnas. Naminé appears and creates a Corridor of Darkness to send them to Destiny Islands. Roxas and her both speak to Sora and Kairi, Sora finally realizes that he has a Nobody, and then their Nobodies return to them.
+ The Corridor closes before Riku and Sora can go through. Xemnas is still alive, and they both defeat him together. Doing so traps them in the Realm of Darkness. Kairi's letter somehow finds them, and the Door to Light appears after reading it. They return home.
+ Afterward, a letter from Mickey arrives.
+ In Final Mix, Sora can fight Terra's Lingering Will.
⊳ Worlds: 100 Acre Wood, Agrabah, Atlantica, Beast's Castle, Castle Oblivion, Dark Meridan, Destiny Islands, Disney Castle, Dive to the Heart, Halloween Town/Christmas Town, Hollow Bastion/Radiant Garden, Keyblade Graveyard, Land of Dragons, Olympus Coliseum/Underworld, Port Royal, Pride Lands, Realm of Darkness, Simulated Twilight Town, Space Paranoids, The World That Never Was, Timeless River, and Twilight Town/Mysterious Tower.
• Coded
+ Occurs after KH2, but before Mickey writes the letter.
+ Mickey, Jiminy, Donald, and Goofy discover a secret message within KH1's journal: Their hurting will be mended when you return to end it. In order to investigate, they digitize the journal and have a data!Sora look for the truth behind the message.
+ They discover that the journal infested with bugs, and that a figure dressed in an Organization cloak is also inside the journal. Data!Sora now needs to destroy all the bugs while following the cloaked figure.
+ Sora travels to different worlds in the journal, destroying all the bugs that he comes across.
+ Heartless appear in Disney Castle. After defeating them, Mickey and co. realize that they're trapped in the room. Until data!Sora bursts inside. The cloaked figure appears, and it turns out it's Riku. And by Riku I mean, the journal took on Riku's form in order to communicate with them. They were transported inside the journal, and the only way to send them back to the real world is to destroy all the bugs. All of them.
+ Maleficent and Pete enter the journal to use it to conquer all of the worlds. Everyone is full of good ideas. They kidnap data!Riku.
+ Data!Sora goes to Hollow Bastion, where data!Riku is forced to fight against him. After data!Sora defeats him, it's revealed that unless data!Riku gets the bugs removed from him, he'll never wake up.
+ Data!Sora goes inside data!Riku. And the fangirls rejoiced. Completely destroying all the bugs sends Mickey and co. back to the real world, but it in turn erases data!Sora's memory.
+ Data!Riku, who still remembers, reveals that he uncovered the location of the truth behind the hidden message. Because data!Sora no longer remembers what happened, Mickey goes back into the journal, confronts him, and sends him to C.O.
+ Data!Sora runs into another hooded figure. The figure is kind of a jerk. Data!Sora realizes that even though he no longer remembers anyone, there's a pain in his heart when he thinks about them.
+ The figure tries to attempt to persuade data!Sora that he should run from the pain. Instead, he decides to embrace it, and the two fight. It's revealed that it's actually a data version of Roxas.
+ Data!Sora and Mickey encounter Naminé. As it turns out, she was the one who was behind both the mysterious message and the bugs. What a surprise. Data!Naminé informs them that she had to test him to see if he can handle an unimaginable hurt, and this was the only way she could do it because she no longer existed in the real world.
+ She reveals that Sora is the only person who can save her, Roxas, Axel, Xion, Terra, Aqua, and Ven, and that he's the key that connects everything. Data!Sora thanks her, and she disappears.
+ Mickey and co. say goodbye to their data friends, and Mickey writes the letter which tells Sora, Riku and Kairi of what they learned on this adventure.
+ Mickey speaks to Yen Sid. Yen Sid reveals that because both his Heartless and Nobody had been defeated, Xehanort will be returning in full power, and that he's not alone. He also states that because Riku and Sora are not actually Keyblade Masters, they will need to undergo the Mark of Mastery.
+ It's also revealed that they have almost found Ven's heart, and only need to find Terra.
⊳ Worlds: Agrabah, Castle Oblivion, Disney Castle, Dive to the Heart, Hollow Bastion, Mysterious Tower, Olympus Coliseum, Traverse Town, and Wonderland.
• Dream Drop Distance
+ Has not been released yet. Release date in Japan is Spring 2012.
+ Occurs after Coded and before KH3.
+ It will have the Mark of Mastery exam of Sora and Riku. In dream form!
+ Xemnas and Xehanort's Heartless are in it.
+ Neku from The World Ends With You is in it.
+ There are creatures known as Dream Eaters. They're split into two types: The ones that eat dreams and create nightmares, and the ones that eat nightmares.
+ Riku and Sora both have their own set of buddies to help them. Wandanyan, the Koumori Bat, etc. are some of them.
+ Has a lot of gameplay elements from BBS, only with more parkour.
+ /sits on hands for more info
⊳ Worlds: Destiny Islands, The City of Bells, and Traverse Town.
• Kingdom Hearts III
+ Has not been released yet.
+ Will be the final confrontation between Sora and co. against Xehanort.
+ No other information has been released.
⊳ Worlds: N/A