Very good book, serious, a little slow, a little school (but in a good sense). it is a useful reading after (or before) The Kingdom of Carrère. This book attempts, him to answer the question: how is it possible that a sect that had really nothing to it, could win (albeit slowly) and invade the West. The answer is also qualified: some finds (moralism and individualism) and a stroke of luck (a visionary senior Constantin).
