--Bona al la encycla lorica.
Darkening of the Light
The tragic fall of Luminarism was a lengthy process that had its roots in the early priesthood of Luminarism. Though it did not have any specific beginning or end, it ultimately resulted in the "darkening of the light" that was early-age Luminarism, and the spread of very long shadows that stretched across the land, blanketing the world in intellectual darkness and plunging the world into a dark age.
The Corruption of the Mage-Priests
As the religion of Luminarism grew, so did the bureaucracy of their mage-priests. While the original few centuries of mage-priests were by and large inquisitive and innovative, in the centuries thereafter the ranks of mage-priests became co-opted by those who were less curious and politically more conniving, for as the power and influence of the mage-priests grew, so did the tendency for those seeking power to enter their system, thereby slowly but inexorably corrupting it. These incompetent latter-generation mage-priests did not make fabulous discoveries of their own, but under the pressure of a system that extolled the virtues of discovery, they proclaimed false discoveries.
The Circle of Inquirers
As is in the nature of scientific inquiry, these false discoveries did not remain accepted for long. When several such false discoveries came to light as a result of tests by other mage-priests, these false mage-priests became defensive, and accused the latter of intentionally trying to ruin them, and attacked them for being jealous of the former's accomplishments. This caused the priesthood to lose face in front of the masses, resulting in a crisis of confidence. Many among the priesthood proclaimed that this crisis would result in the unraveling of the priesthood and that their golden era would therefore come swiftly to an end; those who challenged that claim were attacked, implied to be agents of the destruction of the priesthood.
As a result of this political maneuvering within the bureaucracy, and the stated urgent need to restore the masses' faith, it was declared that none may publicly challenge the proclaimed discoveries of any mage-priest. Instead, such accusations could be brought forth to a panel of only five members, called the Circa Incuira, or the Circle of Inquirers, whose task it was to determine whether or not these allegations were factual, by performing tests of their own to verify the truth. In the meanwhile, the accuser could not let anyone else know of these allegations. Established in 621 AL, the Circle was made small so that few would have access to the potentially disruptive information and to lessen the chances of such accusations leaking out. And when the Circle found the accused guilty of fabricating a discovery, it was promulgated that the accused would be punished in secret, by removing them from their role in the priesthood and to lock them away in a dungeon to rot away. In this way, it was reasoned, the priesthood would not be doubted by the populace.
Luminarian Silencing of Accusations
As a result of the corrupting policies of the mage-priesthood, public accusations of fabricating discoveries dried up, and soon all that was ever heard and said of the mage-priests was their great curiosity and inventiveness, and nothing was said of how some among them were corrupt. And so in the shadows of the religion of illumination, corruption grew.
Starting in 625 AL, those who made accusations of false discoveries were taken before the Circa Judicara, or Circle of Judicators, to be judged for breaking the ongoing gag order, and generally stripped of their titles and publicly flogged, so as to discourage any others from making public accusations. This was ostensibly done in the name of preserving the image of the priesthood. Those who brought these claims to the Circa Incuira would have their way for another hundred years, but for much of that time at least one member on the Circa Incuira was a corrupt mage-priest, who worked to silence the accusers: they would leak out the names of the accusers to the accused, and thereafter the accusers oftentimes found themselves blackmailed, kidnapped, or killed. Before long, the mage-priests began to notice this pattern, and soon very few people approached the Circa Incuira with accusations.
Eventually, in 727 AL the Circa Incuira proclaimed that any who would bring false accusations would themselves be punished, and publicly, should the accused be proclaimed innocent. The five members of the Circa Incuira all became bribed to simply always proclaim the accused innocent, bribed by those corrupt mage-priests who wanted to ensure that none dare challenge them. They succeeded. After a string of high-publicity punishments of the accusers for experiments that some mage-priests could verify independently, it was blatantly obvious to the mage-priests that the Circa Incuira was totally corrupt, yet there were so many corrupt mage-priests voting to keep them in office that they remained in power. Almost no accusations of false discoveries would be brought before the Circa Incuira starting 734 AL.
Persecution of Accusers
The mage-priests who remained true to the original cause, unable to seek recourse via the Circa Incuira, turned instead to the masses, teaching them to be inquisitive and doubtful and showing them the lies of the false mage-priests. Of course, the men under the control of the Circa Judicara hunted down many of those people. To facilitate the hunt for the accusers, the priesthood branded them heretics in 766 AL, making the holding and spreading of unorthodox beliefs a crime. As many of the mage-viziers of the Luminarian empires were corrupt mage-priests, they convinced their luminarates (kings of the luminances, the empires of Luminarism) to hunt down these heretics, that they may not spread their "lies".
By 800 AL, only a single luminance did not persecute heretics, and all the heretical mage-priests congregated in its capital city. When that capital city was sacked in 824 AL by the other luminances upon the urging of the priesthood, in a war of "internal" Illumination, all the heretics were rounded up and executed, and all the true mage-priests knew that there was nowhere left to hide from the corrupt mage-priests.
Consequences of the Darkening
With the suppression of discovery verification and the resulting retardation of technological advancement, and subsequently the overt prosecution of those who honestly searched for the truth, fewer and fewer people joining the ranks were truly interested in scientific inquiry. Instead the ranks of the mage-priests over the years became more and more filled with the false mage-priests, who told of false discoveries and ordered troops to hunt down any who would say otherwise. As the mage-priests ceased to make new advances in science and technology, they became jealous of those who did; they proclaimed others' discoveries as their own, then killed them. The pattern of behavior was not lost upon would-be inventors, and invention practically ceased by 825 AL.