Frateris Militia
From Lexicanum
The Frateris Militia are masses of the faithful gathered to fight wars of faith against enemies of the Emperor and mankind. They constitute the unofficial and generally ill-trained troops who fight, indirectly, in the interests of the Ecclesiarchy. Although most such mobs consist of no more than faithful Imperial citizens, some "brothers" have had military experience in the Imperial Guard or a PDF. They make up for this general lack of military training with selfless fanaticism.
In battle they are barely organised, except in huge mobs consisting of any number of militia brethren. Mobs vary from ordinary Imperial citizens incensed by Confessors to zealous self-sacrifice, to the already fanatical members of extreme Imperial religious sects. Such is the brethren's devotion and willingness for self-sacrifice, the more dangerous and desperate the fighting, the more likely they will fight to the death.
The Crusade of the Red Redemption (or more commonly, the Redemptionists) is one of the most notorious of these extreme religious sects. Their creed is one of violence, paranoia and xenophobia, seeing humans as inherent sinners, unless proven otherwise. As a militant sect, they frequently gather to fight wars of faith.
