Doom Retcon Timeline

Background
The bulk of this timeline is based on the apparent retcon made by Doom RPG's website, and Doom 3: BFG Edition manual which apparenlty places classic doom in the 22nd century alongside Doom 3. The original versions of Doom 1-3 did not have specific dates for when the games took place (only implied to take place in 21st century due to the novel series, and manual for Doom port for the SNES, see Doom Timeline).

Classic Doom (Original Doom Games)
(Includes Ultimate Doom, Doom II (Master Levels & No Rest for the Living), Final Doom, and Doom 64, Lost Levels of Doom 64.)

(In Addition a few elements from Doom 3 and Doom Reboot (2016/VR/Eternal) are nodded to as well).

If Doom follows Doom 3, then the date given in the original manual of classic Doom, would place the events of the game roughly 3 years after Doom 3. If that was the case, here is the order of events following Doom 3.

It is assumed the events chronicled in the Doom 2 manual about the attack on Mars Base, are the same as events in Doom 3.
 * 2145
 * May (128) (parallel universe?)
 * The first Project Lazarus Manned Expedition is sent to Hell. The expedition ends with complete loss of human life, but achieved its mission. The sarcophagus of the Doom Marine is recovered from Kadingir Sanctum.
 * November 15
 * Our Hero (B.J. Blazkowicz) arrives on Mars on Transport 4409 as punishment for assaulting a superior officer for ordering his soldiers to fire upon civilians, and to replace another soldier. He and his body cast were shipped to Pearl Harbor, while the Marine were transferred to Mars, home of the Union Aerospace Corporation.
 * Soon after there is an invasion from Hell, he is one of the only survivors.
 * 2148
 * Doom - The Doom Marine (B.J. Blazkowicz) spends the next three years cleaning up the mess at Mars Base, at Mars radioactive waste facilities. He is sent to Phobos after a distress signal is sent. He is forced to again fight demons on Phobos, Deimos, and then in Hell itself.
 * Doom II - A Doom Marine heads to Earth from UAC Mars Base in a drop pod and sees that the Demons have begun conquering Earth.
 * No Rest For the Living - The Doom Marine stops another invasion by traveling to a Hell pocket universe to destroy another Cyberdemon from amassing an army.
 * After Hell's catastrophic invasion of Earth, the United States took steps to try to prevent another invasion from occurring. The old UAC corporation was re-founded, though it survived most its top level management had destroyed. It was turned over to strict government supervision, under completely new management (Final Doom).
 * It began to research tools and technologies to prevent future invasions from happening again (The Plutonia Experiment). With Earth invasion stopped, the remaining demons were gradually exterminated by mopping-up squads. The new UAC began working on quantum Accelerator devices, intended to close interdimensional gates at a distance and prevent future incursions. Scientists began to work with Gate technology again in order to learn how to close the Gates. This drew attention from beings from Outside. A new Terror began as a Gate was opened up in the research complex. But the scientists were ready and closed the gate with their Quantum Accelerator Device, closing it instantly and permanently. The next day another invasion struck using seven Gates, while six of the gates were closed, the marines were not able to hold out, and everyone was killed.
 * The Marine who had been put on leave on a beach near by the complex was called in by the government to fight back and recover the Quantum Accelerator and destroy the Gatekeeper guarding the last Gate of Hell. Being the only Marine left with no backup for an hour or two, he had to stop the Demon's plans or it would be too late. He took on the horde, to stop the Gatekeeper, and prevent another demonic invasion of the world.
 * The new government supervised UAC set up a new base on one of the moons of Jupiter, as it continued its research into matter apportation and transportation under increased safety measures. They had hoped increased distance would enhance Earth's safety if something went wrong, and marines were stationed at the base, ready for anything (Final Doom: TNT: Evilution).
 * 2149
 * The Invasion of the Jupiter moon base began not long after the opening of the first Gate. The United States Space Marine Corps were prepared and won the battle. Research continued but less cautiously...
 * Several months later, believing that yearly supply ship was on its way, were caught in surprise as Demons attacked and invaded from space via flesh and metal mother ship. They were unprepared to fight an attack from above.
 * The Marine, now the Marine Commander was the only survivor left, as he was miles away from the base taking a stroll on the moon's surface at the time. He heard the sound reminding him of the nightmares he still had (from his previous battles with the demons). He returned to the base to discover his men dead, and vowed to take revenge (TNT:Evilution).
 * The Marine's (B.J. Blazkowicz) fatigue was enormous, his price for encountering pure evil (no mortal was meant to experience hell). The military doctors submitted him tests and treatments, which were of little help. The nightmares continued. In the end by planetary policy, all was classified and sealed. The installations were sealed, and abandoned, and absolute quarantine guaranteed by apocalyptic levels of radiation (Doom 64).
 * Mother Demon survived in radiation of bombarded planetary space installation. Shielded in the radiation it resurrected the demons mutates them into stronger and more vicious forms.
 * October (past or parallel universe?)
 * Doom (2016) Begins
 * Doom Eternal
 * Years Later
 * Doom 64 begins. The Doom Marine is re-commissioned to stop 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.
 * Doom 64 Lost Levels begins. A new chapter in the Doomguy's saga, taking place shortly after [Doom 64's] original campaign concludes. The Mother Demon the marine defeated, had a sister, and Doomguy has been messing up Hell non-stop, she tried to get rid of him by sending him away back to a base on Earth. He makes it back to the sister in Hell and take's revenge.
 * Doom 64 Lost Levels ends. The Marine had not expected to be torn from Hell so soon after his fateful decision. Getting back there was his only concern. The plans of the sister Resurrector to exterminate him had failed. A grim vision took hold of his mind as the demon carcasses steam in his wake. Stretched before him is was a path of perpetual torment... A path through DOOM...