I have been reading a lot about morals and how it has evolved with humans across different cultures, and apparently it has been lately when morals actually were involved with religion. Anyways, I was wondering whether there is any known existing or extinct culture that was never religous? I mean, do we know whether at least one tribe ever progressed without having religion as part of their culture and life? Or is it religiousness kind of a natural and inherent part of us as humans that only progress and further cognitive developments proved as unnecesary (and actually against knowledge) for us?