Dark Age of Technology
"In ancient times, men built wonders, laid claim to the stars and sought to better themselves for the good of all. But we are much wiser now."
- – Archmagos Ultima Cryol - Speculations On Pre-Imperial History
"The Day Science begin to study non-physical phenomena, It will make more progress in one decade than in all previous centuries of its existence"
- – Nikola Tesla
The Dark Age of Technology (or just the Age of Technology) was a period of history before the Imperium of Man, where human civilization flourished and spread throughout the stars. It takes place shortly after the discovery of the Warp-drive and the Navigator gene.
Thanks to the discovery of the Warp drive technology, Geller Fields allowing for Warp travel (alongside the heavily implied "design" of the Navigator sub-species. There are several hints throughout the books that they did not evolve "naturally") and the Standard Template Constructs, humanity was able to spread far and wide, settling millions of planets and driving out the xenos-civilizations that came before them. The result was akin to a golden age for humanity, with technological marvels (beyond even the Adeptus Mechanicus's ability to
recreate comprehend) being constructed, and laws of physics being re-written.
The Age of Technology ironically ended because humanity had become too dependent on their technology and on Warp travel. They lost the former with the rebellion of the Men of Iron, and the latter as the increasing emergence of psykers and the uncontrolled release of their powers (as they did not know how to control them, let alone shield themselves from the Warp, making them either convenient focal points for daemons to enter real space, or turning them into them power-hungry, possibly Chaos corrupted slaver-kings as it happened on numerous worlds during the Age of Strife), and Eldar partying too hard caused Warp storms. Enslaver plagues wiping out entire populations due to the increasing number of Human psykers and the resulting (aforementioned) close encounters of the daemonic kind on various populated human worlds and spacecraft (think "Event Horizon") throughout the galaxy further accelerated the downfall to this "first" human empire preceding the Imperium. With humanity struggling to battle the backlash of this sudden mayhem, aliens long thought to have been driven off, or who lived under the benevolent care of the human empire came back / rebelled for that sweet sweet vengeance. Thus, humanity fell into a period that would later become known as the Age of Strife. Interestingly the emergence of psykers in human strangely coincides with the gestation of Slaanesh.
The "Dark" in "Dark Age of Technology" is kind of misleading, as it implies that the Imperium considers technology to be inherently evuuul. In truth though, one of the major reasons why humanity uses the term "dark" is that - during the Age of Strife - which was characterized by civil unrest, daemonic incursions, including but not limited to depopulation of whole planets, Warp travel / communication becoming impossible (resulting in complete isolation of human populated worlds, disintegrating what was left of the first intergalactic human civilization) all of this combined led to the first major loss of previously obtained knowledge. Following this dark era the wars of the Great Crusade, and in particular the Horus Heresy, followed by the long millennia of the Age of the Imperium (which - as we all know is characterized by unending war on all sides, superstition, xenophobia, etc) finally resulted in destroying basically all records of the Age of Strife and the Dark Age of technology, respectively, that may have been preserved until then, leaving only scraps of knowledge and rumours behind.... or as Kasper Hawser put it in the Horus Heresy novel "Prospero Burns": "Do we even know what we have lost? or something like that. Needs a proper citation). The Horus Heresy certainly did not improve on the situatio. To come back to why the Dark Age of Technology is called "dark". In part this is for one due to the above mentioned circumstances - Humanity simply knows next to nothing about this era anymore. The closest thing we know how Humanity may have lived during this Age were the Interex, a civilization that was more advanced than the Imperium, but was unfortunately wiped out at some point by the Luna Wolves, the war starting with Erebus secretly stealing an Anatheme (the very same warp-corrupted sword that was later used to mortally wound Horus in order to engineer his corruption) from one of their museums. This convinced the Interex the Imperials had been corrupted by Chaos already, leading to the start of hostilities. However, it is also called "Dark Age", because it is now considered a spiritual dark age compared to the "glorious modern age", as humanity used to put science first (which may or may not have caused the birth of the Omnissiah - probably not - but the Void Dragon imprisoned on Mars by the Empra is a hot candidate. Also highly ironical considering the Emperor wanted to get back there with his whole "Imperial Truth" idea), rather than the God-Emperor of Mankind. The irony of all this is lost on every human in the setting. The only remnants of the technological wonders of that age (called "archeotechnology" or "archeotech," which the Adeptus Mechanicus furiously seeks), are the STCs, which could be the Imperiums' salvation. Other creations of that age, like the Men of Iron, are best left forgotten (or better yet, destroyed). Pfft... good luck getting a tech-priest to not poke around the possibly-dangerous ancient technology, though.
Highlights of the technology that has been hinted at canonically include still-pristine warships with bridges made of solid light, something equivalent to time-weapons, and a cloud of sentient nano-machines that can kill you by making your blood explode. Dark Age of humanity wasn't nothin' to fuck with.
TL;DR: It's basically Star Trek meets Atlantis.
List of reasons why the Dark Age was kickass
A.K.A. why the Emperor is kind of a failure.
- Widespread immunity to all diseases and poisons (The Panacea).
- Far more widespread use of anti-gravity.
- Guns that can travel their ammo back in time so they can hit their target with 105% accuracy and shoot blackholes.
- Robots with the strength of Space Marines that numbered in levels close to the Imperial Guard.
- On a similar note, Sentient AI's. Or close enough to it to be highly capable but not close enough to be people.
- Imperator Titans were practically universal in most planets' PDF.
- Average humans performing really hazardous duty like deep space mining or maintenance of a voidship's plasma coils had access to Terminator armour. Well, not exactly Terminator armour as the Space Marines use; but those incredibly durable exoskeletons-cum-spacesuit that were used by civilians while performing their day job back later served as the template from which Terminator armour was developed by the AdMech. After they recovered a bunch of them during the Great Crusade, they only had to add auto-senses, black carapace interfaces and whatchamallicks to allow a Space Marine to use the suit like a regular set of Power Armour.
- Weapons that could shoot enemy ships in the middle of a warp jump.
- Something like DC Comics' Nth Metal made by Human technology (invented after Psychic Powers are scientifically proven to exist after being used as the poster boy of IRL pseudoscience)
A basic Fanon timeline of the Dark Age of Technology http://www.heresy-online.net/forums/155-homebrew-40k-fluff/211473-fanon-history-dark-age-technology.html#post2375305