In the twelfth century, an Italian monk named Joachim caught the attention of the Christian West by announcing the Three Ages of the World. Joachim arrived at his formulation by a meshing of the Christian Trinity with the Old and New Testaments, proclaiming--in sequence--the Age of the Father, the Age of the Son, and the Age of the Holy Spirit. In the early modern period, however, archaeologists uncovered the remains of an agrarian village social...