Fan timeline

This article contains timeline of dates from various fan, third-party commercial level packs, and other unofficial mods, in relation to Classic Doom series (based on the classic Snes Doom timeline).

Background
Romero is said to have once said all Doom Wads are 'canon', but take place in alternate universes.

That being said, fan writers and developers would have you believe that Earth has been plagued with both alien and demonic, and heavenly invasions for some time since possibly midieval times, throughout the 20th century, and many times in the 21s century and beyond. UAC's and portal research can even be traced back to Nazi Germany, where Hitler was using ancient portals to travel to the future and steal technology from UAC, or even an attempt to change the future (wining the war and expanding across the solar system in 2043), so that they ruled it(Spear of Destiny Expansion Packs, The Portal/Astrostein series).

UAC appears to be behind the alien and demon invasions time and time again. Every time the events get covered up by UAC and whoever is ruling on the earth, and new stake holders of UAC begin the research anew. Doing more experiments as if expecting different results, the exact definition of insanity.

Several of these games/mods/add-ons such as Sigil, Winter's Fury , Double Impact , Eviternity , along with Plutonia Experiment, and TNT: Evilution (originally part of stand alone "Final Doom") and No Rest for the Living are offered as 'Add-ons' with Bethesda.com's PC, PS4, and other console releases of Doom 1 and Doom 2.

Some materials from the novels are included as characters such as Flynn Taggart is used in severl mods, wads and megawads.

Flynn might be canon to the game series or at least the reboot: There is a book the shelf about Flynn Taggart's biography, there is also a company named Taggart Comics Group. Entering  'FLYNNTAGGART' onto the old computer in Doom Eternal, will unlock DOOM 2.

This may suggest the reference to Flynn Taggart's escape to earth from Deimos Base in mail rocket in Hell on Earth novel is a reference to the Marine (Doom II)'s escape to earth using a drop pod in Hell on Earth manual. Though depending on the source Doom II hero is same hero from Doom/Doom 64 aka Doom Slayer/B.J. Blazcowicz. While other accounts seperate the two characters from Doom and Doom II into two different persons. For there to be other marines who survived one would have ot ignore the references to 'only survivor', as Fly Taggart escaped with Arlene Sanders back to earth. Doom II marine at least is implied to be the only survivor of a concurrent Mars Base invasion (much like Doom 3 Marine), while Doom 1 character (Doom Slayer/B.J. Blazkowicz) was only survivor of Ultimate Doom scenario in Doom (surviving Phobos/Deimos and finally Hell). However the fact Taggart and Arlene made it through Phobos and Deimos would also contradict the 'only survivor' claim. However, its possible that most of UAC never knew as Flynn mostly was on his own 'secret missions' in the novels (since he and Sanders disappeared into the future by time dilation for all UAC knew, both were dead), and would have been recorded as such in their records.

Timeline

 * 12, 974 BC
 * An alien race existed in a distant galaxy, a race of beings that had mastered ways of mixing technology with the power of the mind. These were the overseers of the universe, protectors of developing worlds, and masters of incredible technologies. Yet, possessing such technology led to conflicts with savage alien races, including a race of monstrous demonic aggressors. A war ensued between the savage demon race and the alien overseers. The overseers attempted to make peace with the attacking force but their attempts ended in miserable failures. The savages were a race of pure evil, no understanding of diplomacy or peace. In a desperate final attempt at suppressing the aggressors, the overseers closed down their most valuable technology, the inter-dimensional teleporters. Before all the teleporters were powered down, legions of the demonic race made their way through, wreaking havoc on under-developed, formally protected worlds. One of those worlds was Earth, many thousands of years ago. The sight of raging monstrous creatures to villagers and peasants in Earths biblical times bred fear in the minds of all. Eventually, the small unsupported armies of monsters were destroyed, but the advent of these creatures rooted myths into human culture about demons from hell and perdition. After the destruction of the initial demon force, myths and legends were all that remained regarding the existence of the creatures. Thousands of years of evolution followed as the people of Earth began to forget about demonic myths and legends of the past while heading headstrong into the technological era. At the same time, the demons took over the former overseer's world, and began their understanding of the overseer's awesome technology. Masterminds were bred to help teach and integrate the demon technology with that of the overseers. Not until recently, did the demon race possess the power to re-commission the inter-dimensional teleporters. Thanks to the efforts of human experimentation on the moon of Phobos, the teleporters on the overseer's world were given life once again. Soon after, the demon masterminds began to understand the workings of the overseer technology and started building attack forces to continue their conquest of the universe.
 * 1621 - Gallieo discovers Jupiter.
 * 1939 - 1945 - WolfenDOOM (Doom)/Wolfenstein 3D/Spear of Destiny/Wolfenstein RPG
 * 1943 - The Mystery of the Marie Celeste
 * 1954
 * December 11th - A base in Greenland is attacked by mysterous monsters from beyond.
 * December 12th -Henry Mills, USMC is posted to Weapons Research Station 46-A in Greenland. Assigned to Head of Security, Special Projects. His plain crashes killing both his pilot and copilot, and he discovers no signs of anyone at the base, and signs of an attack of some kind. He assumes the Soviets were able to attack the base before he arrived. He decides to search for a radio and warn the American Forces of what happened. Entering the base to look for survivors, he discovers that Hell Demons have invaded the base.
 * December 13th
 * Henry Mills defeats a cyberdemon, and stops the invasion. He finds a note saying that source needs to be destroyed, or Earth will be invaded again someday. A secret organization steals an artifact, and covers up the events of the invasion.
 * December 19th
 * Eisenhower believes based on survivor's testimonate, that it was attack of biological warfare by the Soviets. He denounces the actions as being 'unprovoked'. He calls for an end of such wawaepons being used by teh Soviet Union, and demands Soviet Premier Kruschev that no more such attacks be made on United States facilities.
 * Kruschev dies all Soviet involvement in the attack on the US military resarch facility the previous week.
 * December 30th
 * Escavation is completed at the site, the General Robertson is told that the primary concern is the sterilization of the site. He is told to raze the site from the air in order to ensure full containtment, which will be explained to the media and general military community. The organization plans to assasinate Sergeant Mills and Master Sergeant Malloy (US ARMY).
 * 1955
 * September 16th
 * US Troops move into East Berlin, overcoming Soviet resistance and seize key points.
 * November 21st
 * Soviets capture radar station in Eastern Europe, and U.S. forces are held captive. This is in response to U.S. military agression.
 * 1956
 * February 24th - The Project has advanced several of its key goals (including getting US and Russia to further distrust each other). Organization staff report to their enclaves in anticpation of the next phase of the Project which they anticipate would begain within the next three months, and last for a duration of five to ten years. A t which point they would implement the final pahse of their plan.
 * June 18th
 * Eisenhower advices civilians to report to designated emergency shelters, as they believe Russia maybe planning an attack.
 * Organization leaders believe its time to finally implement the primary phase of their project.
 * 1973
 * March 20th
 * 1991
 * Researchers at UAC Plant 6 begin work on some form of teleportation technology. The military got wind of it, and poured millions of dollars into it.
 * 1992
 * The researchers wer eon the verge of a breakthrough. They artifically created a void portal inside the Research Lab itself. They began to experiment with the portal, and military supplied a live volunteer.
 * 1993
 * Wolfendoom (Wolfenstein) - B.J. Blazkowicz Jr, son of the legendary World War II hero of the same name (William J. Blazkowicz), and apparently the uncle of Commander Keen] (Billy Blaze II). Employed as a military consultant at the Union Aerospace Corporation (UAC), you become involved in a race to close down 6 portals to another dimension, nicknamed the "Doom Dimension", opened up inadvertently by UAC Research personnel. He traveled across the United States to each site, to close the portals. After his work they hire him to become Senior Military Advisor to the UAC.
 * Salvation backstory.
 * 1995 - Gordia
 * 2000
 * B.J. Blazkowicz Jr is promoted to General Manager of the UAC on Earth.
 * 2002 - 2002: A Doom Odyssey: You have fought your way through that monster infested bloodbath to destroy the spider. Then you return home to find out the awful truth that you're wife "Stephanie" has been kidnapped by Tommy the Trooper. Your mission is now leads you back into hell in order to seek and destroy Tommy and rescue you're wife.
 * 2010
 * B.J. Blazkowicz Jr retires from UAC. ON his last day Research Lab technician bursts into the office, and explains that UAC had discovered a method for teleportation technology. B.J. was concerned that things might go wrong after what happened the last time they worked with teleportation stuff. B.J. decided he wouldn't authorize any experimentation, since the risks to Earth were to great if something went wrong. He is told that its out of his hands, as the military agreed to set up experimental teleportation facility at their remote planetary outposts Phobos and Deimos. In case something went wrong, they believed Earth wouldn't be in danger. B.J. warned that it wasn't a very wise course of action, but the military was already making the decisions.
 * 2012 - Meanwhile, aliens known as Freds steal Deimos stole Deimos some four years before, hiding it hyperspace/dimension. Some time later (in 2012), Flynn Taggert, Arlene Sanders and their Fox Company squad are called to Phobos from Mars after distress signal given. They find the base swarmed with demons, and most of Fox Company are killed. Flynn and Arlene find a transporter that takes them to lost Deimos. They discovered it had been converted into a massive space ship and was hurtling towards earth. Fighting their way through the base (and slowing the aliens plans), it finally reappeared above earth (it rested in low orbit above the planet). They could see that the demons and aliens had already invaded Earth. Three weeks later they jerry-rigged a mail-tube rocket out of spare parts, and used it to crash-land back on Earth.
 * 2013 - Salvation
 * Another attack on Earth by demons,"total global war" between humanity and an invading race that "attacked with a fury that seemed the spawn of Hell itself" is stopped and covered up.
 * Flynn Taggart and Arlene take part in this c. 2012 Doom War helping clear aliens. They discover information about the Freds and decide to head into space to stop them. They won't be seen again for around 501 years.
 * 2018 - By 2018 Mars UAC restores Deimos to an orbit around Mars, and rebuild their bases on the moons.
 * The military, UAC's biggest supplier, has used the remote facilities on Phobos and Deimos to conduct various secret projects, including research on inter-dimensional space travel.
 * 2019 - The Marine (B.J. Blazkowicz (Doom) (grandson of William Blazkowicz, and son of B.J. Jr)) assaults a superior officer, and is transferred to Mars, home of the Union Aerospace Corporation.
 * 2021 - Salvation: A Marine is sent in to investigate Environmental Protection Agency's offices to discover if there had been another invasion.
 * July 1 - DOOMNL 01-D19305-1C is published.
 * October 15 - Lone scientist is sent on a scientific journey to the outer Solar System
 * 2022
 * March 15 - Mars receives a message from Phobos base stating that the base is under attack and requesting backup.
 * A few hours later, the marines land and try to stop the invasion. The Marine is ordered to stay behind and protect the perimeter. The marine forces are wiped out or turned into monsters. Planetary authorities send the final Marine the new DOOMNL 01-D19505-1D replacing earlier manual (now including briefing for the Marine, and images from the invasion captured by remote video cameras. The video data was computer analyzed by the UAC and the results are provided "here and only here") . The Marine leaves the escape pod vowing to take down as much of the invasion force as possible before death.
 * Knee Deep In the Dead begins as the Marine arrives in the Hangar Atrium.
 * Meanwhile... Double Impact begins. You’re a UAC mechanic, knee-deep in fixing corporate hardware in the maintenance area as demons from Hell bust loose looking for human souls to devour. Seeing as you’re a mechanic, when s*** hits the fan, you take the fan apart and FIX THE FAN! He attempts to escape to the Hanger, so he can flee the base.
 * Knee Deep in the Dead ends as the Doom marine is ambushed by the forces of hell upon arriving on Deimos, and presumably dies.
 * Shores of Hell begins as the Doom Marine finds himself alive (or resurrected) somehow, and pushes against the forces of Hell.
 * Shores of Hell ends as the Doom Marine rappels down the surface of Deimos, discovering that it is now orbiting above Hell itself.
 * The Lost Episodes of Doom - Meanwhile on Callisto, Io, and Jupiter.... You're the lone occupant aboard a utilitarian deep space probe returning to Earth. Your six-month reconnaissance mission of the outer Solar System is over and you're finally headed back home.
 * Inferno begins as the Doom Marine arrives on the surface of Hell.
 * Inferno ends with the Doom Marine killing the Spider Mastermind, the general of the Phobos and Deimos invasions, and 'rewarded' with a gateway to Earth discovering Earth has been invaded and his pet Rabbit is killed.
 * Thy Flesh Consumed begins (an interquel of sorts inserted after Shores of Hell and before or during Doom II). The Doom Marine continues to fight in revenge for his dead pet Daisy stopping the Spider Mastermind's invasion force 'before' it is sent to earth. But he is unable to prevent Hell on Earth.
 * Doom: The Lost Episode
 * SIGIL begins (the interquel continues) After killing the Spiderdemon the Marine's next stop is Earth — he must save it from hellspawn that has causing unimaginable carnage. But Baphomet glitched the final teleporter with his hidden sigil whose eldritch power brings the marine to even darker shores of Hell. He fights through this stygian pocket of evil to confront the ultimate harbingers of Satan, then finally return to become Earth's savior.
 * Meanwhile, a Marine stops a demonic invasion on the UAC Mars Base on Mars over the course of a few days. He is given leave to return to Earth. He was the only survivor on Mars. He returns to earth in a drop pod only to discover it has been invaded by the Demons from the Outside.
 * Demon Eclipse - Just a few months ago, you were a proud sergeant within the military. Your life took a turn for the worst when your convoy ran over a mine and you ended up in the hospital, barely alive. But you're tough, you made it through and recovered eventually. However, when you went back, they told you were no longer fit enough to be in command. Thanks to your past accomplishments, the military decided to cut you some slack. They referred you to the UAC, a global corporation that is the leader in technology research and currently runs the show on Mars. The UAC is known to have a contract with the military and supplies them with the latest prototype weapons; some of which you've used before. They recently constructed a series of facilities on the outskirts of the desert to "cut down on research costs". Who knows why they built the thing? You landed yourself a job as a security guard. Driving around the UAC compound 50 times was an usual day's worth of work. You were bored out of your mind and felt that your life has ended at the age of 30... then the incident happened, and your life was once again changed forever. From out of nowhere, a distress call came from Mars, where the UAC was doing its most shadowy research - Something about demons invading through portals and all sorts of mumble-jumble. Mars was apparently under attack by an unknown force and the UAC wasn't ready to lose the red planet for anything. They gathered up a group of the toughest marines and decided to take the place back from whatever attacked them. It was also an opportune time to test out their new gateway system that linked the two planets. Just as the gateways connected, and the marines were about to go through, a giant spider-like creature stepped through. It ripped the marines and scientists in front of it apart with his two massive auto-cannons while causing massive destruction from what seemed to be a BFG 9000. A horde of strange creatures followed it through the gate and reeked terror on the unsuspecting marines. The creatures quickly took over the gateway control facility and fanned out to the nearby compounds quickly. Many were slain only to have their corpses somehow reanimated. You were on your 10th loop around the UAC compound when you got radio distress calls for back up. You did what you knew how to do best - kick ass. You fought you way through to the command station to see what was going on. News of the incident reached out fast and the UAC compound was locked down within a matter of hours. All roads to and from the site were shut off and anyone trying to go in or out was shot on sight. When you made it to the command station, you learned of the gateway and the beasts running through it. You didn't know what to make of it. Then you heard from the military about the quarantine policy and it involved nukes. You didn't survive the mine just to be killed by army's own nukes now. The only way out was through that gateway. You don't know where it would take you, or if you were even survive long enough to get to it. But anything is better than being turned into radioactive vapor. You gathered all the ammunition you could find and prepared for the fight of your life...
 * Doom II begins
 * Going Down
 * Hoover Dam
 * Master Levels for Doom II/Maximum Doom/PSX Master Levels campaign
 * Phobos: Anomaly Reborn - Marine (B.J. Blazkowiz) returns to Phobos to end yet another invasion on newly rebuilt Site A and Site B.
 * No Rest for the Living begins
 * The Doom Marine continues his battles on Earth after Hell's forces were seemingly vanquished, and is forced to travel to a pocket universe to stop another demonic threat.
 * Mother Demon survived in radiation of bombarded planetary space installation. Shielded in the radiation it resurrected the demons mutating them into stronger and more vicious forms.
 * After the human race evacuated Earth, it was decided to bomb the entry points of the invasion from space. Following this, "special military teams" were sent to take out the surviving forces.
 * Doom Resurrection (WAD) - Our Hero retires from the Marines to go work for Core.
 * 2023
 * Nearly a year later, the human race returned to their now devastated planet and began to rebuild, amidst occasional but ongoing battle with the remnants of the enemy. In the wake of the invasion, the newly arisen United Nations established the Earth Defense Council (EDC), which would protect the planet from future invasions. Fulfilling this is the Earth Defense Force (EDF), their active arm, consisting of every military force in the world, which also explores nearby planetary systems for life forms hostile or not.
 * The Union Aerospace Corporation is entirely reformed, as the original stockholders, trustees and management were killed in the invasion of Earth, and begin managing two projects; one in an unknown jungle, and the other on one of the moons of Jupiter.
 * Yearly supply ship reaches Jupiter's moon. Demons use it to invade the UAC base there.
 * TNT Evilution begins with the Doom Marine, the last surviving marine Jupiter moon base, once again fighting against the forces of Hell.
 * TNT Evilution ends with the Doom Marine destroying the Demon-spitter.
 * The Quantum Accelerators in the jungle succeed in their maiden test, however, next day seven gates opened throughout the base by the forces of Hell, six were closed, but the armies of hell were too strong, too numerous, killing everyone in the base. The forces of hell took control of the Quantum Accelerator.
 * The Plutonia Experiment begins as the Doom Marine fights against the forces of Hell again after arriving via pickup truck.
 * The Plutonia Experiment ends with the Doom Marine destroying the Gatekeeper, swallowing up the final demons and the accelerator.
 * Plutonia 2
 * Memento Mori - Hell's invasion of Earth has left three quarters of the human race dead. Nuclear warheads carried by colony ships were used to seal the portals of Hell, leaving most of Earth uninhabitable. Now, Doom's protagonist is in his home town, where the invasion began, to assist in the planetary reconstruction effort. This seems to be progressing smoothly, with a jury-rigged radio in a makeshift headquarters set up to enable communication between cities. On day 372 of reconstruction, however, a message arrives from headquarters: contact was lost with a city in the center of the United States. Subsequent reports from ill-fated scouts reveal widespread violence and destruction caused by demonic figures. It seems there is one portal from Hell remaining, one missed during the twilight of the invasion. Satellite imagery reveals that this portal is in the center of the city.The protagonist, the only man with enough experience fighting Hellspawn, is recruited to track down and destroy the portal, and then slaughter the demonic horde that arrived through it. He is flown by a salvaged helicopter to the city, as close to the portal as possible. As soon as it turns to leave, it is shot down by a rocket. The protagonist must complete his mission alone.
 * The exploration has been going via short-range cruisers, equipped with Personnel Transport (PT) systems developed by the UAC for direct travel between ships and planets. Two have reached their destinations and have sent back preliminary scans suggesting no signs of intelligent life, with more data expected as the exploration teams are planned to do surface scans soon.
 * 2024
 * Memento Mori II - Since the destruction of the last portal from Hell, the reconstruction of the devastated Earth has gone smoothly; contact has been restored with the outer colonies of Earth. On day 727 of the effort, Doom's protagonist, overseeing the construction of suburban homes, is visited by a car carrying General Kimmel and Lieutenant Bates. The protagonist is ordered into the General's car, where the Lieutenant gives a prepared briefing. Headquarters has had contact with the colony on Io, one of the moons of Jupiter, since three weeks prior, where they learned the colony was starting to run low on supplies and received "anomalous readings" from their last probe to Jupiter. No further communications were heard until a distress call came from the Io colony. Following this, headquarters dispatched a team of agents to scout Io; they arrived about a week prior to the briefing, and reports started to come in two days before. Many have not come back. It would appear that Hellspawn have infested Io, and it is up to the protagonist to kill them. A ship is ready to take him to Io in the next hour, with little available weight and space meaning supplies are limited. Faced with the choice of remaining on Earth for the reconstruction effort or being trapped on Io "with only a pistol and the cries of the dead to keep [him] company," the protagonist agrees to take on the mission. He opens a metal box on the seat next to him to reveal the briefing module, a notebook computer containing the scouts' reports, which reveals the mission is codenamed "Memento Mori, Operation Two" (Memento Mori was "Operation One"). The General translates the Latin name as "a death's head, a reminder of those who died in the invasion."
 * Icarus: Alien Vanguard - Doom's protagonist is woken up at 2:00 AM by a call from his commander, General Bill Robinson, for an emergency, which sends him on a flight to the Northern United States EDF base near Billings, Montana. There, he receives the news: it seems the EDF has lost contact with the Icarus, the last exploration cruiser to be launched, headed for the Beta Pictoris system. It was exploring and scanning the five planets2 of Beta Pictoris as planned when, according to its logs1, scanners detected intelligent life on the third. Analysis revealed Beta Pictoris 3 to have Earth-like conditions, and a recon team was sent to the surface. Unfortunately, the team encountered hostile life forms six hours after landing, resulting in an almost half-hour firefight in which the hostiles were apparently killed along with several members of the recon team. The bodies were brought in for analysis by the Science branch of the Icarus. The last log entry, around five hours later, reveals the hostiles were playing dead, and subsequently took over the ship using the PT systems to increase their numbers. The entire crew of the Icarus was seemingly killed. Asked by the protagonist when he is scheduled for takeoff, the General informs him that the EDF has nothing capable of reaching the Icarus or Beta Pictoris 3. What it does have is the location of a storage depot in Florida once owned by the IRS, which included a fully functional "hyper-shuttle" among other spacecraft and armaments. However, it was overrun by the invasion forces early in the conflict, and EDF has not taken it back since. One soldier (or a small team) is to sneak into the depot, reclaim the shuttle, fly it to the Icarus and eliminate all hostiles aboard. The protagonist is the one assigned to this mission, which he accepts gladly. He has a "jump-jet" prepared for him, scheduled to launch at 11:00 AM. Before dismissing him, however, the General informs the protagonist of two things. Firstly, the shuttle only has enough fuel to make it to the Icarus and not the return trip, unless the protagonist can refuel from the Icarus. Secondly, the Icarus must be returned with none of the hostiles alive. If it appears this is impossible, the protagonist is to activate the self-destruct and escape. With both of those points understood, the protagonist leaves to prepare for takeoff.
 * Daedalus: Alien Defense
 * The fatigued Doom Marine is decommissioned, and the military DOOM Episodes are classified. The UAC's planetary bases are sealed, and quarantined by radioactive bombardment.
 * 2026
 * Perdition's Gate - You are a cadet marine who has been called upon to serve in the UAC strike force while they continue running controlled gateway experiments at their Earth headquarters. Arriving at the main gate on your first day of service, you notice that things don't seem to be running normally at the UAC headquarters. You pull out your service handgun, and enter the main gate suspecting the worst. Little do you know, but you are about to embark on a journey to the overseers world, the dawn of a new battle on another plane of existence. Hopefully, you have what it takes to clean out the alien world, and find the portal leading to the plane of hell itself; hopefully, you can find and destroy PERDITION'S GATE.
 * Doom 64 begins (a few years after Doom II)
 * The Doom Marine is re-commissioned to stop and the latest invasion, he stops the Motherdemon's forces which had been building in the former battlegrounds he failed to clear.
 * Doom 64 Ends. The Doom Marine decides to stay in Hell to prevent the rise of another demon lord after destroying the Motherdemon.
 * The Lost Levels begin.
 * The Lost Levels end.
 * 2053 - Winter's Fury
 * A few years have passed since the first Demon invasion (Doom1 and Doom2). The UAC is on constant watch for activity of demons on earth and mars. The UAC have been completely paranoid that more demons could come at any moment, and are researching new technology to stem the invasion forces, such as the Ion Cannon on Cybergaze 2.1x, or even the Hellfire Fuel at the Insanity's Edge Mining Complex, not to mention their other secret projects that you, Sergeant Major Elliott Morse, shouldn't know about. You are a part of one of a vast amount of Specialist teams, know as the T.A.O (Tactical Assault Operations), designed to find and hunt down remaining demons on earth.The latest signal has come from Siberia, inside a mountain named Mt. Baphomet, where ironically, the remains of Baphomet are sealed in a vault far below the mountain. Within and around the mountains perimeter are hundreds of Pre-Demon war facilities that the UAC took as their own during the first war against the demons. All information about the base has been classified since. A minor team was sent to deal with this signals inconvenience. That team never returned. Now, the UAC are beginning to panic. However, they have no wish for the T.A.O to clean this mess up for them... Fortunately, the T.A.O can go right over their heads on this one. Currently commanded by Colonel Andrew Luke, this team makes no mistakes. You are part of this team, after showing outstanding skill in all areas. You didn't think you were that good. The leader of Alpha squad in your team, and friend from the Demon War, Corporal Markus Dirnberger, believes that the UAC did genetic experiments on demons here. You also owe him 17 dollars. You think he is crazy, but with the UAC, you can never know. The T.A.O all know from first hand experience, that the UAC always lie. For our mission, they want us to go in, find the problem, terminate it, and get out. Simple, huh? The general expects us to follow these orders exactly. Yet what the UAC actually have done here has saved the lives of millions... ...But now has condemned the life of your team, and possibly the rest of the earth to the demons. Or something much worse.
 * 2099 - Doom 2099 - You are half-cyborg. Most humans are in this year...
 * 2145 (Doom 3/Doom Resurrection/Doom RPG/Doom 3 TC mods for Doom/Doom II, Doom RPG TC mods for Doom II/Perfected Doom 3/Doom 3: Phobos)
 * 2146 (Resurrection of Evil/Doom II RPG/Doom 2 RPG TC mod for Doom II)
 * 2148 - After the events of DooM 3 resurrection of evil, a new evil has arisen. The forces of evil now will not have the Earth as their main objective, but those who humiliated him in the past. Let revenge begin! Revenge of Evil consists of five, challenging, levels for the campaign of the first episode called "forces of evil" plus a sixth level that is the opening of episode two called "requiem of evil."
 * 2149 (Doom 2016), Doom VR, Doom Reboot TC conversions for Doom II.
 * 2163 - Doom Eternal
 * Someone (Jill Lovelace?) writes Flynn Taggart's combined biography: Ret-conned: The Life and Times of Flynn Taggart. Flynn himself is still chasing after the Freds somewhere between Fredworld and Earth.
 * Taggart Comics Group is named in honor of the lost hero (and probably has published versions of Jill Lovelace's stories).
 * Doom Slayer seems to be a fan of Flynn Taggart, even going as far to use it as his computer handle/log-in ID.
 * 2174 - Action Doom
 * The Union Aerospace Corporation is in over its head. On a remote island in the Gulf of Mexico, the United States Goverment funded the construction of the top secret UAC Site 4 Labs. They were to be in charge of the work the government was unwilling to show the public. Originally, the base was constructed to investigate extra terrestrial lifeforms buried deep beneath the surface of the earth. Recently however, scientists and army officials together have begun teleportation experiments... into other dimentions. Using this newfound portal technology, the United States Government has created a gateway into Hell itself. Now, never content to just sit idle, scientists at UAC Site 4 have begun genetically altering demons brought back from hell, with the DNA from the Aliens found at the crash site. It has been a week since any contact has been made with Site 4, and the government has only one option left, the men and women of the most elite government task force known as I.M.P.S.E. It's up to you to discover what happened to the UAC Installation.
 * 2184 - Action Doom 2: Urban Brawl:
 * ...a drinking ex-military guy who lives in Saigon with his daughter alone in his flat, after wife passed away. After a day of binge drinking in the park, he comes back to his home drunk, just to find his door half-open instead of shut and locked. Upon storming inside, he see that some business-man type professional assassiner taking away his daughter, also threatening him at gunpoint. Before our hero can clench his fists, he goes unconscious because of being intoxicated and possibly a blunt impact to behind of his head. After getting up, he understands that the man and his daughter are gone and now his house is lit on fire to remove any trace of evidence.
 * 2212
 * Two hundred years have passed since a lone marine stood against the forces of Hell. Bone weary from the conflict, and thinking they were finally safe, mankind shunned the ways of war and devoted themselves to turning Earth into a paradise. Near Jupiter, a worm hole opened. A vast alien armada quickly established on Io, Jupiter's volcanic moon. Without warning, the alien fleet descended upon an unsuspecting Earth. Many rushed to greet the alien visitors, only be dismembered by the killing machines disgorged by the hellish alien ships. It was soon obvious that the aliens were bent upon savage colonization. Some even tried to defend the planet, but it was hopeless. Billions died. They were the lucky ones. Those that remain bowed down before their new metal masters and meekly accepted the living Hell that awaited them in the Slave Pits. The physically fit were pressed into labor under inhuman conditions. Those who weren't or who could not perform to the satisfaction of their masters were led away never to be seen or heard from again. No one really knew what happened to them, but there were rumors too horrible to believe.
 * 2222 - Hell to Pay
 * But it wasn't the metal demons who were feared the most, rather the sadistic and twisted among you who were led away only to come back transformed into trustee guards. The way they looked at you with a hunger in their eyes was enough to send shivers down your spine. But unlike the other slaves who have given in to fear, you have let the hate burning in your heart give you strength while you waited for your opportunity to strike back. But the worst has happened, one of your fellow slaves whom you told of your plans was turned into a trustee. You have been arrested and thrown into a holding cell. The opportunity you've been waiting for hasn't arrived. The other slaves had been looking towards you to lead the revolt. As the trustees lead you away, you saw in their eyes that they had lost of hope. As the trustee opens the cell, you shudder as you remember the rumors of a "Final Solution". Filled with rage, you slay the trustee with a savage blow. You grab his pistol and emerge from the cell screaming, "There's gonna be HELL TO PAY!"
 * 2513
 * Endgame ends - Flynn Taggart  returns to Earth after centuries of FTL  travel after (subject to time dilation) defeating the demons allies beyond Solar System. On Earth he learns many humans are still alive (many are trying to maintain a peaceful existence based on Socialistic Society and Mormonism). Much of the former United States is ruled by the People's Great Republica.
 * UAC is still around though, and still in league with a renewed US military.
 * Super Doom - The earth's gonna be changed to hell and the demons' coming through the portal. Loads of people are screaming in fear as the monsters kills them. Everyone thinks the earth would be destroyed. Flynn Taggart, returns and he have to save the earth from the demons.
 * EarthBound Doom - Flynn Taggart is promoted to General. Sometime later he travels to a parallel world where he assists heroes in defeating an invasion by Serpent Riders. He is able to return back to his universe in the end...
 * Claustrophobia 1024 2: The Mystery of Too Many Maps - Taggart sails to Orion.... (more FTL travel, and more time dilation)
 * Claustrophobia 1024 2: The Mystery of Too Many Maps - Taggart sails to Orion.... (more FTL travel, and more time dilation)


 * 3022
 * Mars War - It is a thousand or so years in the future and you are a Martian terraformer stuck in a small station in the middle of nowhere. Since the beginning of the terraforming project, the United Organizations of Earth have been threatening to take control. They do not like the independence that Mars has gained and view Mars as a threat. The United Organizations of Earth are an accumulation of all governments, large corporations, and corporate owned governments of Earth. For over a hundred years they have tightly controlled the population of earth, at an almost microscopic level limiting what they are allowed to know and what they may do. A few months ago, a huge number of radical, highly educated people escaped UOE persecution by coming to Mars in a large space-warp capable ship they built more or less by themselves without the knowledge of the UOE. This was the last straw for the UOE. They attempted to quickly clone the space-warp technology and sent off an invasion force. Only something went wrong with their new "space-warp" capable ships...
 * c. 4,00s
 * Taggart returns to Earth from Orion (after much more time dilation).
 * Operation: Biowar - The president of the UAC makes an alliance with a high ranking demon codenamed TCHERNOBOG, which has resulted in the souls of all UAC workers being sold to the demons in exchange for an unlimited amount of live demonic biological weapons. Flynn Taggart, the protagonist of the original Doom novels, is killed by the UAC and it is up to the new protagonist to put an end to this new diabolic scheme by finding and destroying TCHERNOBOG once and for all.

Behind the scenes
The Icarus log entries in Icarus: Alien Vanguard, are dated to 2024, suggesting that the events of Doom II took place in 2012 (as the backstory talks about a war on earth 12 years before). It could just be coincidence but this 2012 date appears to coincide or is based on the time frame given in the classic Doom novelizations. Which place events of Hell on Earth around 2011-2012 roughly a decade before the SNES Doom timeline placement of around 2022-2023.

There are additional Taggart references although they wouldn't really fit into this timeline without some massive 'time travel' happening. Since Flynn Taggart only got back to earth in the 2500s in the novels. He couldn't have had time to make Taggart Comic Group.
 * Flynn Taggart creates Taggart Comic Group which publishes comics that focus on the DOOM invasions (during his life and later invasions).