If there's one topic that gets humanists excited it's religion. Odd, really, as we're supposed to have left it behind. But religion is more than a collection of superstitions, rules and peculiar habits. Religions have been integral parts of most past and current societies. Religion matters both for its influence on individuals and the way it shapes societies.
So here is a book that deals with the social dimension:
Big Gods: How religion transformed co-operation and conflict.
Princeton University Press, 2013.
Norenzayan's thesis is that the great monotheisms became dominant because they enabled societies to become bigger and thus able to dominate their competitors. The imperial and expansionist histories of Christianity and Islam, though not of Judaism, certainly support this view though earlier large empires didn't seem to need it.
But, for me, Norenzayan's most interesting points relate to the step after monotheism. He says that strong state institutions, such as police, can substitute for the all-seeing Jehovah God. A few societies, mostly in Scandinavia, have outgrown God and their people behave well without his presence. They have, he says, "climbed the ladder of religion and then kicked it away".
In the UK religious belief is in free-fall but we have not achieved the Scandinavian Utopia. Perhaps the truth is a bit more complex than Norenzayan thinks.