As the political center of the Roman Empire shifted east, Constantine also tried to reorient his new religion, Christianity, toward the east, holding the first church council in Nicaea in 325. The idea was to get all Christians to believe the same thing. That worked, but it did mark the beginning of the emperor having greater control over the church. That trend would, of course, later lead to tensions between the church centered in Constantinople and the one centered in Rome, but more on that in a bit. To give you a sense of how dramatic this shift was, by the 4th century CE, Constantinople's population had soared, while Rome's had gone from 500,000 to 80,000. And although the Byzantines spoke Greek, not Latin, they considered themselves Romans, and if they did, we probably should too. Let's go to the Thought Bubble.