ID multiverse timeline (Doom 3 as sequel)

The ID multiverse timeline is a concept created by the developers (principally Tom Hall and John Romero) of the ID games in which many of the games created ID are part of a larger multiverse (either a single timeline, or parallel worlds connected together) as discussed by Tom Hall (see Canon or canons). It appears in the lore of Quake Arena/Live/Champions series (from 1999) and Doom/Wolfenstein RPG series (from 2005) series as well. The crossover elements first appeared in backstory for B.J. Blazkowicz from the Wolfenstein 3D guide which tied B.J. to Commander Keen, but to a lesser degree with the inclusion of Nazi 'created' (according to the interlude text) portions of Hell in Doom II.

Background
According to John Romero and Tom Hall, the B.J. Blazkowicz (original series not the Machine Games reboot), Commander Keen, and Doom Marine from the original Doom (Tom Hall only worked on the original Doom) are all connected in the same timeline. They have said that Doom Marine from the series is a descendent of Commander Keen either his son or grandson.

However Doom II's marine may or may not be the same character or a separate character from the Doom I character depending on different manuals and websites. His backstory differs from that of the original Doom character in that he fought on UAC Mars Base and escaped in a drop ship (mirroring events of Doom 3). Whereas as original Doom character fought in Phobos and Mars and in both original Doom and Ultimate Doom reaches earth via transporter gateways.

In 1999 game Quake III Arena, the Doom Marine ("Doom") appears alongside other ID multiverse characters in which according to the backstory takes place in the Arena Eternal a battle ground with champions brought across the universe and time and space (it was one of the first appearances of the multiverse concept in an iD game).

The connected UAC Website itself was a tie-in to both Doom 3 and the Doom RPG lore. Wolfenstein RPG (2008) utilized Tom Hall's backstory that B.J. was an ancestor of the Doom Marine character/s. Deimos is missing indicating a nod to missing Deimos in the original Doom. However, the placement of Doom II is not clear, the Doom II marine may or may not be the same Marine as that in the original doom (depending on source). Doom II's backstory indicates that he was a survivor who fought back demons on UAC Mars Base (a plot mirrored in Doom 3, and again in Doom RPG) and landed on Earth via a drop pod only to learn that Earth had been invaded (this is clearly different than how original Marine reached earth in Doom/Ultimate Doom). So either Doom II's character is a seperate person (who existed in parallel to original Doom Marine), or that these are in reference to two different invasions at different points in time (which could technically place Doom 1 before Doom 3, and Doom II after, and Doom RPG after both Doom 3 and Doom II). The exact date for Doom II has never been given, but many fans assume it to be directly after Doom/Ultimate Doom (interpreting the endings of the game to be a direct proloque to Doom II despite the differences in backstory for the Doom II character).

Similarly the Doom 3 BFG Edition manual implies that the characters from several games are the same individual, and they represent his adventures):


 * Step into the boots of DOOM Marine and experience his adventures for the first time, or all over again. Featuring enhanced versions of DOOM 3, DOOM 3: Resurrection of Evil and the all new DOOM 3: The Lost Mission, plus the classics DOOM and DOOM II, DOOM 3 BFG Edition is the consummate DOOM experience.

Interestingly the introduction seems to go as far to possibly suggest that the marine in Resurrection of Evil is the same marine as Doom 3 (which if true would have to suggest that Marine combat engineer actually did know the nature of the previous incident despite what the manual suggests). However, it also seems to imply that the Bravo Marine in Lost Mission is the same marine, but this is impossible as its timing overlaps with events of Doom 3 (only 6 hours into the invasion).

Some of this may have been ignored or became obselete by new Bethesda games both Wolfenstein (New Order/Old Blood) reboot and new Doom reboot (it is also unclear how much of Doom 2016 even fits with Doom 3 if at all).

However, Quake Champions confirms that the original Doom Slayer is the same character from all (or rather most) of the previous mainline FPS games in the series (going back to Doom 1, Doom 3, and earlier Quake Arena games), but the Terror Billy from Machine Games series is from a seperate universe (and not same character as Doom Slayer's ancestor from Wolfenstein 3-D, but rather an alternate Earth equivalent). Quake Arena/Champions series takes place in the Arena Eternal which is a pocket universe connecting heroes from many universes, across time and space, in an overarching iD Multiverse.

Based on Tom Hall's comments on the Blazkowicz family history the timeline given in SNES Doom, see Doom Timeline (for the classic series timeline) still appears to be fairly accurate. However, how this relates to overall timeline in Doom 3/Quake Series, etc, is not clear, barring explanations of time travel/paradox/time dilation/extreme longevity (medical advancements)/suspended animation, or cloning of the character involved. It would also seem to place at least Doom before the events of Doom 3 (though Doom III's might be an adaptation/retelling of the Mars Base invasion of Doom II's manual). Final Doom appears to take place after Doom II. It's technically unknown how many years Doom 64 takes place after Final Doom, and only that the character in the story was decommissioned, and possibly put under stasis the entire time. It only refers to previous missions as the "DOOM Episodes". It is possible at least from Quake Champions perspective that Quake 64 could have taken place after Doom 3 chronologically, while earlier games took place in after or earlier times.

iD Multiverse
In addition Doom (2016) and Quake Arena/Champion series introduces that there is a multiverse of alternate universes with different earth histories. Characters from these universes are sometimes brought to the Arena Eternal to combat. Thus its possible for characters William J. Blazkowicz and Commander Keen's descendent in one timeline; B.J. Blazkowicz III (aka Doom Guy/Doom Slayer) (who has travelled between 'worlds and time') to meet William J. Blazkowicz ("Terror Billy") from the dark alternate reality (MachineGames) in a place outside of space and time. The exact timelines of these separate universes of the various characters visiting Arena Eternal is not known for every character. Some may even be from the same universes.

The timeline in this article covers the one from the classic iD universe which ties Wolfenstein, Commander Keen and earlier Doom's together (based on Tom Halls comments and various game references). Certain dates for classic Doom are not entirely known, as to order of the games. Some dates place Doom in early 21st century before Doom 3, but other details including what is said on Doom RPG website, and the Doom BFG Edition may place them as later in the timeline and claims its the same character (as also later confirmed by Tom Hall). The intro in manual to Doom II could even be inspiration for Doom 3's plot (which might place Doom II after Doom 3). Quake Champions still states that marine from Doom 1 and Doom (2016) are the same character and that he becomes the Doom Slayer (so while he may not be in his original universe in Doom 2016, he is still the same Marine who descended from William Blazkowicz in his original universe).

One thing of note is that while the universes are connected somehow and especially as seen in Quake III Arena/Quake Live/Quake Champions games. The existence of parallel universes seems to be a possibility as well, with players crossing over from their own universes/timelines which maybe the case for some elements of the Quake Arena games. So while this is a timeline following Allies winning WW2, there also appears to be a parallel alternate reality in the Id Universe where Allies lost (B.J. from the Allies lost reality is introduced into Quake Champions). It's hinted that the Doom Marine in Doom (2016) has apparently fought for aeons across Worlds and Time (indicating he is same main marine from the original Doom games, but has been fighting his war across dimensions and trying to stop more than one earth's attempts at accessing Hell). This is actually confirmed in Quake Champions backstory for the character (which uses much of the same backstory from Doom 2016).

For the timeline of the universe the Doom Slayer travelled to after his body was discovered in Hell, see Doom Reboot timeline.

ID Universe timeline (Doom 3 as sequel)
(Spear of Destiny/Wolfenstein 3D/Mission Packs, RTCW/Wolfenstein, Doom/Doom II/Doom 3/Doom RPG/Doom II RPG/Doom Resurrection, Orcs & Elves I/II, Quake III Arena/Quake Live/Quake Champions, and Commander Keen)

Note: If the original dating in Doom Timeline and implied by Tom Hall's comments are taken into consideration. Doom 1-2 occur almost a century before Doom 3. But the same character is involved in both, and somehow experiences on Earth itself are apparently classified/hidden from the majority of the public (as is stated in Doom 64's manual, however unlike that seems to be), however technically possible as Doom 2 game takes place in a small part of the earth shown (but Final Doom confirms earth was saved from total invasion). See also Doom Timeline.


 * 100 A.D. - Germans begin using runes for magical and ordinary writing. They were able to use runes as a method of gaining insight into the future or the unknown by supernatural means (see Thule).
 * 918 - German Prince Heinrich I begins studying the Thulian Mystery Occults, and resolves to forge his own empire at the expense of the existing Frankish dynasty.
 * 933 - Heinrich I unleashes his army of undead on the invading Magyars, defeating them at the Battle of Riade.
 * 943
 * Heinrich I is sealed within his tomb by Simon the Wanderer.
 * The Defiled Church is built.
 * Unknown Date - The Spear of Destiny is found under Castle Wolfenstein in the catacombs.
 * August 15, 1911 - William "B.J." Blazkowicz is born in America (possibly in Milwaukee).
 * 1918 - End of WWI, the Spear of Destiny is one of the national treasures taken from Germany, and brought to a museum in Versailles, France.
 * 1929 -Geneva Convention bans chemical weapons.
 * 1933
 * Adolf Hitler becomes Chancellor of Germany.
 * Albert Einstein lives in California, but becomes a target of the growing Nazi might.
 * 1934 - The Totenkopf instituted by Heinrich Himmler becomes the symbol of recognition and loyalty to Hitler and his ideals. These were used on rings adapted Pagan Germanic mythology from Thor, and Wotan's spear.
 * 1937
 * Deathshead begins research into Super Soldiers.
 * 1938
 * As early as 1938, it was concluded that Operation Resurrection would require the development of an advanced synthetic humanoid host.
 * A very good year for wine, as the 1938 Latour proves.
 * 1939
 * Nazi invasions begin in Europe. Nazi Tanks roll into France, Hitler's armies retrieve the Spear of Destiny from Versailles, and bring it to Castle Nuremburg.
 * Einstein writes a letter President Franklin D. Roosevelt warning of German's advances in physics and warning of the possibility of Nazis developing a uranium bomb.
 * Operation: Resurrection is put on hiatus, after some major disaster at the Holstein dig.
 * 1940
 * Nazis conquer France (Operation Fall Rot).
 * April 16, 1940: War department records issued for Webley and Blazkowicz.
 * September 21, 1940
 * Jean Moulin briefs William Blazkowicz under a mission for the OSA in France. The French Resistance help B.J. infiltrate Germany. The Spear of destiny is recovered from Castle Nuremburg and demon is destroyed. The spear is brought back to the U.S. where it was kept under tight security.
 * B.J is honored by president Franklin D. Roosevelt for his actions at the White House in Washington D.C.
 * 1941
 * Hans von Schlieffen and a group of Storm Troopers travel to the U.S. to regain the spear. Hitler's forces recapture the Spear of Destiny again, but only the Axe escaped to the Nazi's Secret Scandinavian Base (built to carry out atomic research). Three intelligence agents are killed trying to infiltrate Hitler's headquarters. Admiral Powell of the U.S. navy sends B.J. to recover it.
 * 1942
 * January 10, 1942: Nazis begin working on human gene modification in an attempt to create a super soldier.
 * January 17, 1942: Experiments are successful. Soldiers begin to smuggle out super soldier cocktails to enhance themselves and sale on the Black Market.
 * February 4, 1942: Scientist tries one of the cocktails, and it works.
 * Sergeant B.J. is sent on a mission to stop Nazi forces near Castle Wolfenstein.
 * Olaric awakens from his tomb, kills the Nazis who awakened him, and is defeated for the first time by B.J.
 * Marianna Blavatsky is defeated for the first time, but she later recovers.
 * B.J. defeats Doctor Schabbs for the first time (or one of his relatives).
 * The Axis empire is at its height. While the Soviets battle the Axis in the East the remaining Allied forces damage and distract the Axis in the West until an amphibious liberation of Europe can be mounted.
 * The Allies concentrated their efforts in North Africa. Here the Axis Forces are ken to inflict further defeats and seize control of the oil-rich Middle East. The sands of the Sahara Desert is the first battle field, and hopefully not the last.
 * Over the course of a month, B.J. has his Original Encounter with Hans Grosse at Dresden, early Eisenfaust encounters, and battle with Adolf Hitler at Castle Wolfenstein. False end to the war..
 * July 14, 1942 - Operation Return to Castle Wolfenstein, Letter sent out to OSA agents..
 * 1943
 * 7 February, 1943
 * German signed top secret document.
 * Blazkowicz is reassigned to Libya to help fight against Erwin Rommel.
 * March 9, 1943 - The last Dark Knight is discovered. Zemph begins traveling to Castle Wolfenstein.
 * March 11, 1943 - Zemph arrives at Castle Wolfenstein.
 * March 12, 1943 - Agent Blazkowicz is reassigned to OSA. He and Agent One are sent from Libya to capture Helga von Bulow in northern Egypt.
 * March 13, 1943
 * Finished repairs and calibrations on generators at the dig site.
 * An attempt on Hitler's life is made. Henning von Tresckow asked Col. Heinz Brandt to take brandy on Hitler's plane. The attempt failed due to a faulty detonator.
 * The Axis High Command has ordered a strategic withdrawal from the 'remote and ultimately insignificant' North African theatre and their forces were busy fortifying the Atlantic coastline in expectation of Allied raids and an eventual evasion.
 * The Allies had much work to do before they could hope to mount a successful invasion attempt and had to gain expertise in both beach and parachute landings. Clearly, the next phase of conflict was critical.
 * March 14, 1943 - Blazkowicz and Agent One reach Ras El-Hadid. After failing to capture Helga von Bulow, they steal a Ju52 transport plane and fly to Castle Wolfenstein in northern Germany.
 * March 15, 1943 - Blazkowicz and Agent One are shot down over Castle Wolfenstein. They are captured by Helga von Bulow. Agent One is sent to Doctor Zee for torture and interrogation.
 * March 16, 1943 - Disaster at the dig site. Otto missing. The Royal Air Force raids Berlin, causing large fires and dozens of civilian casualties.
 * March 17, 1943 - Death of Agent One. Blazkowicz escapes Castle Wolfenstein and fights his way to Wulfburg Church. Helga von Bulow Summons Olaric. She kills Zemph and is in turn killed by Olaric. Blazkowicz confronts and kills Olaric (for the second time who had become more ghost like in his new form), and retrieves the Dagger of Warding, a mysterious Thulian artifact.
 * March 20, 1943 - Blazkowicz infiltrates Deathshead's rocket base at Katamarunde near the Baltic Sea, destroys an experimental V2 rocket and a prototype Mark I radar array.
 * March 21, 1943 - Blazkowicz infiltrates Katamarunde Airbase, steals the Bachem Ba317 Kobra plane, and flies it to Malta. That night, he is deployed to Kugelstadt, where he assists in the defection of one of Deathshead's research scientists.
 * March 22, 1943 - Blazkowicz infiltrates Deathshead's Secret Weapons Facility below Kugelstadt. Later in the day he is deployed to Norway, where he infiltrates Deathshead's X-Labs and destroys his first Übersoldat. Deathshead escapes and is promoted to General.
 * March 23, 1943 - Blazkowicz is deployed to Paderborn in the evening. He assassinates top officers of the SS Paranormal Division in Paderborn and in Chateau Schufstaffel. Blazkowicz infiltrates the dig site and returns to Castle Wolfenstein. Marianna Blavatsky resurrects Heinrich I to become the New Reich leader. Blazkowicz defeats the dark prince and terminates Operation Resurrection.

2149
 * 1944
 * July 20, 1944 - An agent attempts to kill Adolf Hitler, with a bomb., however, Hitler survived the attempt.
 * The Spear of Destiny is recaptured by Hitler. Learning from his past mistakes, Hitler has expanded his subterranean command bunker beneath the chancellery in Berlin so that he can keep the Spear of Destiny nearby and well-guarded. Calling upon the dark forces of the occult, he summons Abigor, Hitler can see into the future and obtain the plans to future weapon systems. B.J. is sent to retrieve it again. He discovers, that the Nazi's are working with magic that allows them to see the future (even going as far to steal technology from the Union Aerospace Corporation). B.J. fights his way defeating Hitler's forces, but is transported to the Future onto a UAC Mars Base (c. 2140s). He defeats the Devil Incarnate and escapes. This apparently isn't the last time the Nazi's recapture the spear however.
 * 1945
 * February 1945
 * B.J. stops the German's deadly gas manufacturing.
 * B.J. destroys Operation Eisenfaust completely.
 * Blazkowicz defeats Hitler again. B.J. became a hero, and world famous, and met the President. The war was thought to be over, but the war continues...
 * Spring 1945 - To prevent allies from capturing the Totenkopf rings, Himmler ordered that Shrine at Wewelsburg castle be blast-sealed into the side of the mountain near the castle.
 * April 28, 1945 - The Spear of Destiny is finally captured by Allied Forces hopefully for the last time from Nuremberg. It is said General Patton discovered the spear, and the downfall of Germany began that day. On the same day Hitler committed suicide in the Fuhrerbunker with Eva Braun. It was fabled that the U.S. was destined to succeed Germany as the New World Power once ownership of the spear changed.
 * Operation Nichtsonne
 * The war ends in Europe.
 * October 23, 1945 - B.J. Blazkowicz's ID expires.
 * 1951 - Blazkowicz gets married to Julia Marie Peterson.
 * His son Arthur Kenneth Blazkowicz is born.
 * Date Unknown
 * - Arthur becomes a television host and changes his last name to Blaze.
 * Arthur marries Susan Elizabeth McMichaels.
 * 1982 - William Blazkowicz II is born.
 * 1990-1991
 * William Blazkowicz II (Billy Blaze) age 8 (Billy Blazkowicz shortened) using the alias of one of his grandfather's old WW2 buddies Commander Keen, saves Earth from many threats, even traveling to Mars.
 * 1993 - The date that original Doom was released, its setting and scenario is strangely similar to events that will happen in the future at least a hundred years later.
 * 2015 - Union Aerospace Corporation is founded by Thomas Kelliher on earth..
 * 2018 - The UAC and U.S. Space Marines and military builds the first base on Mars, and its moons, and several other planets. It quickly becomes a multi-planetary conglomerate consisting of many off-world moons and planetary research stations including Tei Tenga, Jupiter (and Europa), Venus, Neptune, Amun and Saturn. . The military, UAC's biggest supplier, begins using 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 III) assaults a superior officer. The officer was shipped to Pearl Harbor, and Blazkowicz is transferred to Mars, home of the Union Aerospace Corporation.
 * 2021 - July 1 - DOOMNL 01-D19305-1C is published.
 * 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 destroy the invasion force.
 * Doom begins
 * Doom II begins
 * No Rest for the Living begins.
 * The Plutonia Experiment begins.
 * 2023 (or at least a year after Plutonia Experiment )
 * TNT: Evilution begins.
 * The fatigued marine is decommissioned, and the military DOOM Episodes are classified. The UAC's bases are sealed, and quarantined by radioactive bombardment. All incursions on Earth are covered up, and its virtually unknown by the public at large.
 * Years Later (Date Unknown, post 2023 or after 2147?)
 * Doom 64 - A relay satellite activates after years of bombarding by neutrons and sends a final message to Earth showing energy signatures unlike anything sampled before coming from the abandoned installations. The classified archives were opened it was discovered that a single entity with vast rejuvenation powers, masked by the extreme radiation levels, escaped detection. It systematically brought he decaying dead back to corrupted living tissue (into something stronger and more vicious than before).
 * As the only experienced survivor, the tough Marine (B.J. Blazkowicz III)'s commission was reactivated and given the order for Merciless Extermination. He returned to a space installation he once saved from demons, forced to kill the beasts again when they are resurrected, he travels back to their world (Hell) where he kills the Mother Demon. He decided to remain in hell to continue to battle the forces of hell to ensure that no demon arises again.
 * 2025 - UAC further makes its name in the famous Joint Mars Expeditions in an attempt to recolonize the planet.
 * October 29, 2095 - Construction of Alpha Labs begins on Mars
 * 2104 - The explorations of the caverns in 2104 led to the discovery of ancient artifact codenamed U1, the Soul Cube, along with stone tablets written by the ancient Martian civilization.
 * 2112 - First structure of the first permanent Martian settlement is built, in what is known as Sector 4 (it is the oldest human colony on the planet).
 * 2114
 * Dr. Jensen received his Ph.D from Union States Institute of Technology, Northeast (USITNE).
 * October 10, 2114 - Birth of Ted Brown II.
 * 2115 - The initial chamber proving life once existed on Mars was discovered in 2115. It leads into what is now known as Site 1.
 * 2120 - Construction on Mars City begins.
 * 2122 - Dr. Kelvin begins working for the UAC.
 * July 17, 2130 - The Alpha Labs are built.
 * 2138 - Dr. Jensen begins working for UAC's Advanced Research Department.
 * 2142 - Dr Jensen begins working on Mars.
 * 2143
 * Dr. Geurard joins the teleportation research team.
 * December 22, 2143 Chainsaw scheduled for refurbishment the following year. Zachary wishes everyone Happy Holidays.
 * 2144
 * Union Aerospace Corporation updates their website.
 * 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.
 * January 8, 2144 Director Castle orders everyone not to tend to anything in the Atrium 02 until they find out what has killed everything.
 * January 12, 2144 - Xanax captures specimens following primary portal grid powerup. He successfully suspends them in stasis for further study.
 * January 13, 2144 - Zanax at the Lunar Outpost receives confirmation from Dr. Geurard on Mars that he has encountered similar fauna in his research.
 * January 16, 2144
 * M. Burns asks Chris to see what can be done about a unit. He couldn't touch the Echo Sierras until his new parts arrived from Earth.
 * J. Klein sees pressure anomalies in the coolant tanks at Cichus, caused by recent power spikes.
 * January 21, 2144 - Zachary looks for inconsistent behavior in computers at Tychus after reports.
 * February 4, 2144 - Zachary can't calibrate flow meters until Mixom tech gets down and serves a tank.
 * February 5, 2144  - Zanax at Keplar Site finds that the creatures are highly resistant to pain and injury, which has made specimen acquisition troublesome. It has been difficult acquiring them without killing them.
 * February 6, 2144 - Zanax research continues. He discovers from field reports that the creatures exhibit varying tolerance for different types of weapon attacks. He indicated that further research would be needed to discover most efficient way of subduing the creatures.
 * February 7, 2144
 * Third repair work order put in for the elevator in Keplar Site. It still hadn't been fixed.
 * X. Zanax on the Lunar outpost classifies specimen as an "imp" or possibly a "Gwocklego" according to his assistant.
 * February 8, 2144 - Zanax discovers that imp is particularly resistant to stasis suspension, but system is stable, but that that researchers should be careful when handling..
 * February 12, 2144 - J.Klein sees intermittent heavy loads on the power griad, but isn't able to find the source yet.
 * February 26, 2144 - Scientists in the Greenhouse at Keplar Site on the moon manage breakthroughs.
 * Febrary 27, 2144 - Cargo personnel begin reporting that their Manifest Database is having issues. A new power supply is ordered to see if it will fix the problem.
 * March 3, 2144 - R. Zachary installs new systems on the UAC Lunar Outpost, and Rhoomba 5000.
 * March 10, 2144 - Upgrades completed by Zachary. Everything checks out ok.
 * March 17, 2144 - Strange things begin happening to machines on the Lunar Outpost.
 * March 24, 2144 - Air, water and septic life supports still functioning but odd data reports. C. Sukut calls in a specialist. Zachary has gone missing.
 * October 10, 2144 - David Kramer forgets to send a birthday present to Ted Brown II.
 * 2145
 * Union Aerospace Corporation updates their website again.
 * February 5, 2145
 * April 5, 2145 - Samuel Harding
 * Dr. Nadira joins the Mars Outpost.
 * June 2145 - Experiment in the Delta Labs triggers an unknown event, resulting in the systematic invasion of the entire facility. Marine forces are deployed to hot spots around the facility, with many teams encountering heavy resistance. Bravo Team was ambushed in EnPro facility while searching for survivors. There was only one survivor of the team.
 * September 5, 2145 - Charles Hollies
 * September 8, 2145 - Pierce Rogers
 * September 14, 2145 - Andrew Chin
 * September 23, 2145 - Elliot Swann
 * September 24, 2145 - James Holiday
 * October 1, 2145 - Nick Sadowayj
 * October 2, 2145
 * October 3, 2145
 * October 5, 2145 - William Banks
 * October 6, 2145 - Karl Cullen
 * October 7, 2145 - Ben Wolfe
 * October 10, 2145 - Ted Brown II receives a birthday gift from Kramer, its hidden in secret room.
 * October 12, 2145 - Karl Cullen
 * October 16, 2145 - Seamus Blake
 * October 17, 2145 - Pierce Rogers
 * October 18, 2145 - Frank Delahue
 * October 19, 2145 - Larry Bullman, Grant Baston
 * October 20, 2145
 * October 22, 2145
 * October 23, 2145 - Gary Ross
 * October 24, 2145 - Frank Delahue, Jack Smith, Henry Nelson
 * October 26, 2145 - Michael Abrams
 * October 28, 2145 - Mark Lamia
 * October 30, 2145 - Bill Tyson, Anthony Garza
 * October 31, 2145 - Mark Lamia
 * Caldex is hired to work on the Lunar Outpost..
 * November 1, 2145 - Mark Lamia
 * November 2, 2145 - Mark Lamia
 * November 3, 2145 - Theresa Chasar (Doom 3)
 * November 4, 2145 - Jeffery Moen
 * November 5, 2145 -
 * November 6, 2145 - Anthony Garza
 * November 7, 2145 - Theresa Chasar (Doom 3)
 * November 8, 2145 - Adam Berneche
 * November 9, 2145 - Marcus Caseon
 * November 10, 2145
 * November 11, 2145 - Michael Abrams, Scott Johnson
 * November 12, 2145 - Marcus Stanton
 * November 13, 2145 - Frank Delahue
 * November 14, 2145 - Marcus Stanton, Robert Finch
 * November 15, 2145
 * Corporal B.J. Blazkowicz (clone of classified hero of a century before (or suffered from 'time dilation', or removed from stasis/suspended animation after being asleep for a hundred years)) is transferred to Mars on Transport 4409, to hold a security position, and to replace a previous soldier.
 * Daniel Young
 * November 16, 2145 - Elliot Swann, Ron Ridge
 * November 20, 2145 - The Recon Zulu marine team found only one survivor, a Marine Corporal. Important UAC personnel such the company's lawyer and counselor Elliot Swann and his bodyguard Jack Campbell, who arrived hours before the outbreak to make an assessment of the whole Mars operation and enact damage control if necessary, were found dead. Master Sergeant Thomas Kelly and other Delta Labs scientists were also found dead. The marine team had no information regarding the fate of Dr. Malcolm Betruger, the chief scientist of Delta Labs who - unknown to them - had become the demon Maledict.
 * The Marine (apparently known as B.J. Blazkowicz (Doom RPG) who survived the attacks in November returns to Mars to investigate strange reports going on there. Research continues at another base, the Mars Outpost. The UAC marinesare involved in the Mars Incident when demons take over the base. He defeats the diaboloical Dr. Kronos and his Cyberdemon creation in a showdown with the legions of Hell. There are no known survivors from the incident (it is not clear where the Marine ended up).
 * 2146
 * May 1, 2146, an orbital probe recorded a faint unidentified signal broadcasted from the abandoned Mars Site 1 complex.
 * August 6, 2146: Date tag on the new Mars mission Goals & Safety video.
 * August 8, 2146, the UAC board of directors announced the renewal of the Mars program, now led by Dr. Elizabeth McNeil, an ex-colleague of Betruger, who had transferred off Mars days before the outbreak and was the original one who requested Councilor Swann's presence on Mars. McNeil's main objective was to continue the experiments on Mars and discover what Betruger unleashed.
 * September 12, 2146: Elizabeth McNeil welcomes personnel to the Site 1 Expedition.
 * November 20, 2146 - Stan Blazkowicz travels to Tycho Station and saves the universe from demons, at one point even defeating the Harbinger, another Cyberdemon his ancestor had defeated centuries before.
 * November 27, 2146: UAC Lead Technology Officer releases the Ionized Plasma Levitator Briefing video.
 * 2147
 * March 17, 2147 - Resurrection of Evil begins.
 * October (Doom 2016) (see below and Doom Reboot timeline).

The GDF is a fencible military, as opposed to the Space Marine Corps which is expeditionary.
 * Outside of Time and Space
 * The Arena Eternal is an extradimensional structure created by the Vadrigar and populated with the greatest warriors in all of time and space. The Doom Marine, and two other survivors of the Phobos invasion, Crash and Phobos, were brought from their respective eras to fight.
 * According to Quake Champions; Ranger the character based on the player in Quake 1 has a photo from 1978, that is 30 years old. Placing Quake in 2008. The first Slipgate may or may not have sent him one hundred years into their future, to 2108. He is also a Vietnam veteran. The comic which gives him further backgroun says he's been trapped in the hellverse since destroying Shub-Niggurath some two decades making it roughly 2128.
 * The Global Defense Force, or GDF, is a supranational paramilitary organization, formed in the mid-21st Century from a large pool of national military organizations and relief agencies, to combat increasingly severe weather events, other natural disasters and terrorist campaigns, as well as to keep the peace in historically unstable regions such as the Middle East. It was created shortly before the Strogg invasion of Earth.
 * The Strogg invaded Earth in the mid-21st Century in search of biological components. The Strogg invaded the Earth in the middle of its 21st Century period, taking its inhabitants completely by surprise. Their large invasion fleet arrived in orbit over the world seemingly out of nowhere, and its ground forces quickly proved themselves a dire threat to the existence of Mankind. By the mid-21st century humanity is fighting for its survival against the hostile alien threat seeking to end the Strogg once and for all by invading their homeworld.
 * How Quake fits into the shared universe is not clear, and there is little work done collecting the dates and timeline from that game and comparing it to Doom series (other than Quake 2/4 appears to take place during the mid 21st century, and majority of Doom takes place in the 22nd century), but could also take place in parallel universes that connect to each other. Doom III Arena's mentions that the Eternal Arena was built "millennia ago" and ties together Doom, Quake 1, and Quake 2 via several characters including Doom, Phobos, Crash, Ranger, Bitterman, Major Wayland, Tank Jr, and Wrack.
 * In addition there are smaller side and alternate timelines from the novels. Note: Bethesda's latest Wolfenstein reboot series The Old Blood and the The New Order which follows Nazis winning WW2 is set in its own timeline as well, but likely doesn't connect to any Doom iteration universe (at least as of yet there is no evidence of space Nazi influenced UAC in the newest game.
 * Note: It appears that Doom Classic may take place "after" Doom 3 in the "iD timeline" due to the fact that Doom 3 marine has the similar backstory as classic Marine. Whereas placing it as a prequel set in the early 21st century would seemingly cause a number of issues (assuming time travel/time dilation/etc is not involved). Noting that Dafydd novels did in fact introduce extreme 'time dilation' (adding 500 years between Doom 2 and the final novel), and Doom 2016 definitely brings up time travel, but if set after Doom 64 would likely cause issues (if Doom 64 is set before Doom 3), unless Doom 64 took place after Doom 3. For it to be the same Marine would make that marine over a hundred years old (or least had to have jumped forward in time via time dilation during his travels). It would also have to assume he either assaulted an officer again, or that the new command decided to return him to Mars for officer he assaulted over a century before. Lastly, 2018-2022 classic timeline dates, predates the joint UAC/Military 2025 Mars Expeditions mentioned in Doom RPG website. Unless there was an even earlier expedition, and the 2025 date was a second expedition.
 * Sam a droid that appears in Doom Resurrection, also appears in Doom RPG. His final outcome is confirmed in Doom RPG.
 * B.J. Blazkowicz from the Germans won 'alternate universe' appears as a character in Quake Champions. The game is a prequel to Quake III Arena and Quake Live, however the exact placement or order of the games it covers and draws from is unclear. It has its own lore , and is set across 'dimensions'.