When we move our focus away from Europe, everything we think we know about Christianity shifts kaleidoscopically, even alarmingly. Let us, for example, take one legendary turning point in the history of Western Christianity. By the year 800, the Frankish king Charles—Charlemagne—had drawn most of western Europe under a single united Christian rule. On Christmas Day of that year, in Rome, the pope crowned him emperor, consecrating the long association of church and state in the medieval West.
