Yale historian Paul Freedman continues his survey of the early medieval world, first finishing a discussion of the Abbasid Caliphate, its capacity to absorb Persian and other cultural traditions, and its decline by the tenth century. He then turns to the seventh century as the hinge point of early medieval history, tracing the rise of Islam, the transformation of Byzantium, the reorientation of Persia, and the disappearance of the old secular aristocracy in the Latin West. The lecture closes with an assessment of the Pirenne thesis, which argues that the Islamic conquests fractured Mediterranean unity and shifted Europe's center of gravity northward. Delivered as part of Yale's HIST 210 course, the lecture moves chronologically through chapters on geography and medicine under the Abbasids, the caliphate's collapse, and the broader argument for the seventh century's pivotal role in shaping medieval Europe.