when the aryan brotherhood first started it was so that caucasion inmates could stick together during a time when there was alot of racial problems both in prison and on the streets. I dont think that the people that originally formed it were really into white supremacism they just wanted a fearsome image and also they probably had generally racist attitudes. They do recruit from neo nazi gangs just because those are one of the groups of white people including bikers that will end up in prison with them.