a timeline of ken's pre-02 life

With how fucked up Ken's memory is...

It's really hard to pinpoint the time at which much of anything happens in his life.

This timeline is my attempt to make sense of his broken memories by incorporating information from the anime, Tag Tamers, and extra materials like model sheets and the Digimon Animation Chronicle, plus my own personal headcanons. While there is a lot of external content, the anime takes precedence, and all extra materials are used primarily for support and added context only.

For clarity, this timeline includes information about Oikawa Yukio that is outside of Ken's experience due to how intertwined their stories are.


bullet points

  • July 16th, 1991: Ken is born
  • Winter 1992-1993: Oikawa Yukio starts work
  • August 1995: Ken witnesses the battle at Hikarigaoka
  • Fall 1995: Ichijoujis move to Tamachi
  • Summer 1996: Ken and Osamu blow bubbles
  • April 1997: Ken starts kindergarten
  • August 1st-4th, 1999: Events of Digimon Adventure
  • August 1st, 1999: Ken's Digivice comes out of Osamu's computer
  • August 3rd, 1999: Vamdemon possesses Oikawa
  • March 2000: Events of Our War Game
  • Late March 2000: Ken first goes to the Digital World
  • August 2000: Ken gives up the power of his Crest; Osamu slaps the Digivice out of his hand
  • Winter 2000/2001: Osamu dies; Ken meets Oikawa at the funeral
  • Early April 2001: Ken switches to private school
  • Late April 2001: Ken and Ryou battle Millenniumon; Ken is hit by the Dark Seed
  • May 2001: Ken receives Oikawa's email and travels to the Dark Ocean
  • June 2001: Ken begins to form his Kaiser persona
  • August 2001: Tamachi Boys FC win the Tokyo Youth Soccer Tournament
  • April 8th, 2002: Digimon Adventure 02, episode #1


now let's break it down...

July 16th, 1991

Ichijouji Ken is born. This is, naturally, based on my general headcanons about his signs and fits with him and Osamu being about two and a half years apart.


Winter 1992/1993 (age 1)

Oikawa Yukio starts working with genetics at a Tamachi computer company.

This estimate is based on Kakudou's notes, which estimate Oikawa is around 30 years old.


August 1995 (age 4)

Ken witnesses the battle between Greymon and Parrotmon at Hikarigaoka and is singled out by Homeostasis as a potential Chosen Child. Due to this, the Crest of Kindness is created for him.

While it is implied in Tag Tamers that Akiyama Ryou's Crest is the Crest of Desire and it is easy to designate Daisuke's as the Crest of Miracles (which I do) and Wallace's as the Crest of Destiny, only the kids who witnessed the battle at Hikarigaoka are given official Crests. Ken's presence during the battle is the only way I can make sense of him having a Crest.

This requires retconning him into some Adventure moments, including the original movie and episode #45 where Homeostasis interrupts the battle between WarGreymon and MetalGarurumon, but Ken's existence was already retconned into the series in many ways by the development team, so I certainly have no issues with doing the same.

Considering that Gennai specifically sends Wormmon to find Ken in Tag Tamers, one of two things happens next: 1) Wormmon's egg, Digivice, and Tag and Crest are dropped in the fray like Tailmon's, but Gennai manages to recover them later; or 2) Gennai keeps Wormmon's egg and everything else instead of leaving it on File Island with the others.

The fact that Gennai is the one who gives Koushirou the information about the growing number of Chosen Children (as explained in episode #39) and yet neglects to mention Ken's existence despite Koushirou's assertion that they want to help any Japanese Chosen Children right away, makes me lean more toward the latter option: Gennai intentionally keeps Wormmon's Digitama and the rest of Ken's things, just as he intentionally keeps the knowledge of Ken's existence from Koushirou and the others.


Fall 1995 (age 4)

As Jou explains in Adventure, episode #29, many families moved away from Hikarigaoka after the supposed terrorist bombing. While all the other Chosen Children's families move to Odaiba (aside from Takeru and his mom), the Ichijoujis move to Tamachi.

There, Ken and Osamu share a bedroom. In Ken's track on the audio drama Original Story -Spring 2003-, Ken says Osamu slept on the top of their bunk bed, and in the Digimon Adventure Character Complete File, Ken claims they took the bunk bed apart and turned it into a loft, but this doesn't make sense with the anime. Ken's loft bed appears to be built into the wall and having a second bed beneath would block access to the balcony, and the shelf Ken claims was put in after they disassembled the bunk bed is present while they're blowing bubbles. More likely, Ken sleeps on a futon that can be put away during the day, which is why the room looks more or less the same in the flashbacks in episode #23.

Mr. Ichijouji starts working at the same computer company where Oikawa is employed. They work in different departments but are on amicable terms.


Spring/Summer 1996 (age 4-5)

This is an estimate for the scene in episode #23 where Ken and Osamu blow bubbles on their bedroom balcony.

The model sheets indicate Ken is four years old at this time.

This same character design is used for the flashbacks where Ken sees how pleased Mrs. Ichijouji is every time someone compliments Osamu - rather, how well they have raised Osamu - and feeling forgotten and neglected, Ken determines he would get more attention if Osamu weren't around.

These events must've happened around the same time, though I'm sure these two things happened relatively regularly at the time.


April 1997 (age 5, grade K)

Ken starts kindergarten at a public elementary school in the Tamachi area. At the same time, Daisuke and Hikari start kindergarten at Odaiba Elementary and Takeru starts kindergarten somewhere in the Sangenjaya district in Setagaya.


August 1st, 1999 (age 8, grade 2)

A Digivice comes out of Osamu's computer, and despite feeling a connection with it, Ken assumes it belongs to Osamu because, as far as he's concerned, Osamu has everything. Osamu, who looks angry despite Ken's claim in episode #23 that he looks sad, puts the Digivice in his desk drawer.

According to the Digimon Animation Chronicle, Osamu is jealous of the fact that Ken is a Chosen Child, but I cannot fathom how Osamu could know what a Chosen Child is, so I disregard this in favor of explaining the anger as him being able to tell from touching the Digivice that it doesn't belong to him.

This happens at the same time that Taichi and the others receive their Digivices at their summer camp and that Hikari's Digivice comes through the Yagami family's computer.

As for the fact that Ken is in 2nd grade in August 1999 but the scene uses his 3rd-grade design: The note on this character design sheet specifically tells the animation team to use this design for Ken's interactions with Osamu, meaning the majority of the events prior to Osamu's death and not afterward.

Is placing this scene in August 1999 pushing the limits of using that 3rd-grade character design? Yes, absolutely. Do I care? Nope.

Besides, this is hardly the only time the series uses one character design for events that happen at least a year apart.


August 1st-4th, 1999 (age 8, grade 2)

Because Ken lives in Tamachi, his knowledge of the events with Vamdemon that occur in Odaiba during Digimon Adventure would be limited, but at age seven and with how close Tamachi and Odaiba are, he is probably aware of the situation, primarily the fog barrier. Due to his Dark Seed-induced Swiss cheese memory, he likely doesn't remember this later.


August 3rd, 1999 (age 8, grade 2)

As the Chosen Children return to the Digital World, Vamdemon's spirit finds a new home inside a depressed and vulnerable Oikawa and takes possession of him in order to find a way to return to the Digital World, as depicted in episode #48.


March 2000 (age 8, before grade 3)

According to Tag Tamers, Ken and Ryou watch the battle against Diablomon together.

But this does not line up with the fact that Ryou is seen in Turkey in Our War Game.

More likely, Ken watches the battle against Diablomon on his own.


Late March 2000 (age 8, grade 3)

Despite the strong but silent implication that Ken should leave the Digivice alone, Ken is drawn to the device, and it is not long after the events in Odaiba that he is no longer able to resist the pull. As soon as he touches the Digivice, he is pulled through a Digital Gate in the computer and journeys to the Digital World for the first time.

While there, he meets his Digimon partner, Wormmon, who is already at Child level. This is how he's first shown in Tag Tamers (and I discussed it somewhat above), and it fits with how Ken doesn't seem to know Wormmon's baby forms prior to 02 and how well Wormmon holds his Child form in the human world while V-mon, Hawkmon, and Armadimon are typically portrayed as their Baby II form.

Ken also meets Ryou for the first time (though this is not the first Ryou has met him), along with Gennai, and finds his Crest of Kindness, but as he missed the battle against Apocalymon, he has no reason to use it. The Digital World is primarily peaceful right now.

On his return, Osamu walks in shortly after he comes through the gate, at which point Osamu slaps the Digivice from his hand and yells at Ken that he's a bad person and not allowed to touch Osamu's things. He demands Ken leave their shared bedroom so he can focus on his homework.

Thinking that Osamu hates him, Ken wishes Osamu would disappear.

The timing of Ken's first trip to the Digital World (and the number of trips he makes) is extremely difficult to pinpoint, and I'll get into it more as we go along.


August 2000 (age 8, grade 3)

The Tag Tamers manual says the game's events take place during summer 2000, thus implying there are several months between the opening scene where Ken and Ryou watch the fight against Diablomon and the main gameplay.

In episode #33, Ken suggests his first encounter with Digimon occurs in August 2000, which ignores the battle with Diablomon entirely, and the Digimon Animation Chronicle says Ken has an adventure with Ryou in the Digital World at that time but doesn't specify the contents of that adventure.

All of this external information confirms Ken's faulty memory in #33 that something happens in August 2000, but it cannot be his first encounter with a Digimon (if nothing else, the battle against Diablomon in March 2000 would count, plus there's my whole Hikarigaoka headcanon) and it cannot be the moment Ken is hit with the Dark Seed (this scene specifically uses Ken's 4th-grade design, the same design used in Tag Tamers, and thus takes place after Osamu's death).

So what is it?

Well, based on the Original Story - The 2½ Year Break audio drama that spans the time between Adventure and 02, August 2000 is my best estimate for when the OG Chosen Children meet Gennai in the Digital World and give up the power of their Crests to free the Four Holy Beasts and restore the Digital World.

As Ken also has a Crest, Gennai calls Ken to the Digital World too, but Gennai cannot physically be with him when he gives up the power of his Crest, as Gennai wants all the kids to do this simultaneously and he is specifically keeping Ken's existence from the others; however, Wormmon and Ryou are there with him. In time with the other kids, Ken gives up the power of his Crest of Kindness so that Wormmon cannot reach Perfect level.

Obviously, Ken still has his physical Crest, just as the OG Chosen would have theirs if the physical Tags and Crests weren't destroyed by Apocalymon.

On the way to Gennai's home, the most likely location for Ryou to take Ken for this important task, they run into a Gazimon and Wormmon scares it off. Afterward, he tells Ken how important his kindness is but how that kindness can easily be taken advantage of and manipulated. Perhaps more importantly, Wormmon tells Ken that the Digivice he has belongs to him and no one else, directly refuting Ken's initial assumption and Osamu's proclamation that the Digivice belongs to Osamu instead.

In episode #23, this scene is shown separate from Ken's first adventure into the Digital World, a flashback he has while in the Village of Beginnings, and while it would be easy to assume this happens during that journey, Wormmon's words carry more weight and meaning after Osamu vocally claims the Digivice as his.

Thankfully, this time, when he returns, no one notices his absence or sees him with the Digivice.


December 2000/January 2001 (age 9, grade 3)

Not long later, Osamu is hit by a car in front of Ken and dies. As Ken's track on the Spring 2003 album takes place during the third spring since Osamu's death, we can surmise that Osamu dies sometime between late 2000 and early 2001.

Ken, because he specifically wished for Osamu to disappear on multiple occasions, blames himself.


February 2001 (age 9, grade 3)

At Osamu's funeral, Oikawa sees Ken for the first time and, due to being possessed by Vamdemon, recognizes his connection to the Digital World and realizes he is a Chosen Child, thus giving Vamdemon the opportunity to enact his plan to reenter the Digital World.

In episode #48, Oikawa says that, when he saw Ken at the funeral, he knew he was a Chosen Child and that there was no other reasoning behind Ken's being singled out.

But when we first meet him in episode #44, he claims he knew Ken has a Dark Seed, and this is supported by the Digimon Animation Chronicle.

Only one of these can be true, and it seems more likely Ken does not have the Dark Seed at this time or Oikawa would have no reason to wait to contact and manipulate him, plus the obvious difference between Ken's design at Osamu's funeral and his design in the scene where the Dark Seed implants in his neck.

As for Oikawa's age and design here...

The anime uses the same character design for August 1999 and for Osamu's funeral and the Digimon Animation Chronicle specifically says this design is from "3 years ago," but the rest of the timeline information does not line up. In all likelihood, the August 1999 and Winter 2000/2001 dates were considered close enough for them to use the same design.


Early April 2001 (age 9, grade 4)

In an effort to figure out what to do with himself now and where he belongs, Ken switches from the public school he and Osamu attended to the private Tamachi Elementary School.

Prior to Ken's 4th-grade design, we never see him, or Osamu, wear a school uniform. Scenes while Ken is in 3rd grade could, of course, take place during a school break, but during 4th grade, Ken wears his school uniform in every scene, none of which take place at his school.

Also, please note that any character in 02 who wears a school uniform is seen in that uniform outside of classes; the only time these characters wear other clothes are during summer and winter breaks or if they're wearing pajamas or a sports uniform.

Therefore, Ken does not attend a private elementary school that requires a uniform prior to 4th grade.


Late April 2001 (age 9, grade 4)

Once again, Ryou calls Ken to the Digital World, and they work together to battle Millenniumon. After Millenniumon's defeat, the dying monster shoots out a number of Dark Seeds toward the group, aiming specifically for Ryou.

Ken pushes Ryou out of the way, and a Dark Seed embeds in the nape of Ken's neck, making him immensely sick, to the point that Wormmon thinks he might die.

He stays at Gennai's home in the Digital World until he is well enough to go home, as shown in Tag Tamers. This is the last time he sees Ryou, and afterward, he thinks Ryou was his imaginary friend (if he remembers him at all).

Ken says this takes place two years previously, which would be December 2000, as episode #43 takes place the day after Christmas. Most people assume this indicates the August 2000 date he mentions in #33 and Tag Tamers, which, again, primarly takes place in summer 2000.

While August 2000 would be reasonably close enough to consider "two years ago," that does not account for the fact that this flashback specifically uses Ken's 4th-grade character design, meaning this scene takes place after Osamu's death. Episode #23 very specifically switches to using the 4th-grade design for all scenes after Osamu's funeral, so having that same design here is an important distinction.

If August 2000 is reasonably close enough to "two years ago," so would an early 2001 date is also within the realm of possibilities, especially since Ken would be 9 here and 11 in episode #43. It also fits better with the character designs, as August 2000 is while Ken is in 3rd grade and Ken graduates to 4th grade in March 2001.

Ken is still rather sick when he returns, as shown in Tag Tamers (and D-1 Tamers, which I primarily ignore because nothing about it fits with the anime at all). As his parents are still grieving Osamu's death, they barely register he's unwell.


May 2001 (age 9, grade 4)

While working on Osamu's computer (now Ken's), Ken receives an email from an unknown source, revealed to be Oikawa later in episode #44.

The email says that he is now trapped in his brother's place and this world holds nothing for him, and to escape his troubled life, it instructs him to take the Digivice from the desk drawer and travel to "a world that will completely free [his] mind."

Oikawa intends for Ken to travel to the Digital World, as Vamdemon is specifically trying to find a way back there, but the influence of the Dark Seed, and the darkness plaguing him, takes him to the Dark Ocean instead. There, he dips his Digivice in the dark water, and it transforms into the Dark D-3 and fully activates the Dark Seed.

You can literally watch the moment the shine in his eyes disappears.


June 2001 (age 9, grade 4)

Now that he is healed after his encounter with Millenniumon and fully under the influence of the Dark Seed, around the time that he is as tall as Osamu was when he died, Ken begins to excel in the classroom and sports. This is, according to his parents, "a long time after" Osamu's death.

Ken starts regularly traveling to the Digital World and begins building his Digimon Kaiser persona to play what he thinks is an immersive video game, somewhere he is safe to explore all of his anger and sorrow and fear without worrying about anyone getting hurt.

Using knowledge from the Dark Seed, Vamdemon, and the Dark Ocean, he builds the Dark Towers and develops the Evil Rings to control the Digimon.


August 2001 (age 10, grade 4)

The Tamachi Boys FC wins the Tokyo Youth Soccer Tournament. During the tournament, Ken scores a total of 45 goals, which is more than twice the previous record of 19 goals.

This likely occurs in August of his 4th-grade year as August is a common time for youth soccer tournaments in Japan due to the summer break.


April 8th, 2002 (age 10, grade 5)

Digimon Adventure 02, episode #1, the first day of the new school year.

This means Ken has only been developing and using his Kaiser persona for ten months or less - not even a year - and Homeostasis and Gennai are most likely aware of his fall from grace before the Dark Towers seal away the Holy Beasts and choose not to do anything about it.


Overall, between Ken's memory problems and the enormous differences between media due to the different teams working on each project, it is impossible to have a cohesive, definitive timeline of Ken's life prior to 02, and there is a lot of room to play with different scenarios. But generally speaking, unless otherwise stated in my fics, this is my go-to timeline.