The Illuminati were Satanic. But not in a modern sense. Most people picture satanic cults as devil-worshipping fiends, and yet Satanists historically were educated men who stood as adversaries to the church. Shaitan. The rumours of satanic black-magic animal sacrifices and the pentagram ritual were nothing but lies spread by the church as a smear campaign against their adversaries. Over time, opponents of the church, wanting to emulate the Illuminati, began believing the lies and acting them out. Thus, thanks to the church, modern Satanism was born. Good job.
The Illuminati were survivors of prosecution. they fled Rome, from the church, and travelled across Europe looking for a place to regroup. The Illuminati grew more powerfull in Europe, and set their sites on America. They had infiltrations, among which were George Washington and Ben Franklin. Their ultimate goal was...a "New World Order", based on scientific enlightenment. they called it their "Luciferian Doctrine"the church claimed Lucifer was a reference to the devil, but the brotherhood insisted Lucifer was intended in its literal Latin meaningbringer of light, or "Illuminator".