(Although its historical enigmas are apparently insoluble让步状语从句),( there is谓语) abundant testimony主 to the vast influence定语 exercised by the book状语 (since the earliest times and in surprisingly varied social contexts状语).
译:
虽然它的历史之谜显然是无法解开的,但有大量的证据表明,这本书自最早的时代以来,在惊人的不同的社会背景下发挥了巨大的影响。
(译文:来自有道)