When conspiracy theorists described the New World Order or the Illuminati, pick your pet name, they always described it as a single cabal manipulating global affairs to their own end. It was revealed that this order had their own name, the Sovereign Order. Make no mistake though, the Order was not so unified. There was no honor among thieves for these individuals. They sought, not only to seize power from the larger population, but also for each other. The Order's dominion was feudalistic in nature. Lesser members would run the lesser desired portions of their dominion and pay tribute to the higher ups. However, this system was, unsurprisingly, not liked by all.
Subfactions were not uncommon in the Order but one stood out among many. Many of the more rebellious members bolstered its ranks soon after the culling and it splintered to forge its own dominion. The Illuminati, as they'd become known either jokingly or as truly descended from the ancient order, were less interested in enslaving the world's population as they were in exterminating it. This was mainly because they sought to use their secret technology and scientific knowledge to push for a cure for their mortality.
These two powers clashed and sought to achieve very different views of world domination and their armies were very different in turn. The Sovereign Order as previously hinted at, wanted to cull a large portion of the population and enslave the rest for forced labor. Their army was created from the perfection of human cloning in secret. Their clone army of mindless soldiers would've easily dominated any army on the planet, not that it needed to because by the time it was created. The Order had secretly turned most of the planet's armies into mindless drones using drugs save for the few people in these armies that were immune, which were easily pacified. While a their legion had the backbone of an army, a large portion of it was built for intimidation. Large tanks and terror-inducing weapons were common.
The Illuminati chose a much different approach. While they used similar drugs to seize total control of the regions they inhabited, this force largely acted as an auxiliary to their main army which consisted of drones. Not mind-controlled clones, but robotic drones. They used an army that was almost entirely automated. Using next generation encryption, it was almost entirely impervious to tampering. The central AI, called the Eye, either for comical purposes or because they'd been sucked into their own mythos, effectively trumped most of the Order's strategy. If it weren't for the resistance's interference and the Order's size, it's very likely that the Order would of lost the war between the two great powers.
Ultimately, the war between these two acted as a smoke screen to protect the resistance as it was largely ignored by the two powers during the war. The Illuminati were the first to fall. The Eye was targeted on the Order's army and their auxiliaries weren't able to fulling stomp out the resistance before they'd become too organized to be stopped. Once the Illuminati's technology was in the hands of the resistance, the Order fell into disarray shortly thereafter. The Eye ultimately destroyed though and their drone army dismantled as it was seen as a threat to humanity itself. The Order's remaining members still hold onto hope that they'll see there dominion realized once again, but the resistance has turned it's priorities away from fighting their army and toward securing global order.
AUTHORS NOTE: I'll need to rethink Madison Lawrence's backstory a little bit. I added the immunity bit to include her, but I'll need to think the mutiny bit.