Ancient Wars
The Ancient Wars were a brutal sequence of events led by a group who named themselves as Arbam's Army. Their leader, Lord Arbam, was incredibly charismatic and radical, leading to him gathering soldiers and men from all across Legere. His army was little more than an enormous mob of people, but with sympathizers in nearly every major city. He led his followers to believe that the Ancients had been corrupted and would soon turn into excutioners of the Legerian people, and that they must be destroyed before they wipe out the planet! Kingdoms everywhere were quick to surrender their Ancients to Arbam and his followers in order to avoid potentially greater civil unrest.
The execution of an Ancient was a diabolical, sad scene. At night, hordes of Arbam's soldiers gathered, celebrating drunkenly as they tore the machines limb from limb, spilling their sapphire blood over the ground. The Ancients did not fight back, programmed only to destroy targets that threatened the realm as a whole as opposed to drunken, confused men. Forbidden to harm those they were built to protect, the Ancients quietly went to their graves as Arbam's men spread word about their "glorious battles" against the cosmic robots.
Even many years after the events of the Ancient Wars, the general populace still believe the lies spread by Arbam. The gist of Arbam's alternate history was that the Ancients were powerful god-machines that were sent to protect Legere from Demons, but over time their minds broke. This caused them to become filled with murderous fury, attacking and burning villages of innocent people. Arbam and his followers bravely fought against the tyrannical mechs. The Righteous Order often tries where it can to correct this false information, but it's very hard to stop the spread of legends.
The only places that were free from Arbam's major influence were the Eastern Provinces. The Ganpoumi Fi were quick to remember the Demon Wars and dismissed the rumours propagating through the lands, leading to the Holy Pact of the East.