If I remember my Asimov correctly:
There were lots of bishops, but the bishops of the most prosperous and powerful towns were the most powerful. That meant that the bishops of Constantinople, Cairo, and Rome were the top three, a leading triad, a triumvirate, or maybe a father, son, and holy ghost. To the extent that anybody was in charge of the church, it was these three.
Then Cairo was conquered by Rome, and lost all of its importance. So then there were just two bishops that--if they weren't all equal--seemed to outrank the others. Rome and Constantinople were the leading partners and rivals.
Part of why they were rivals was because symbolism doesn't work the same for everybody. In the east, the priests wore beards, and so, to the western priests, they looked like German barbarians. In the west, the priests were clean-shaven and celibate, so, to the priests in the east, they looked like eunuchs.
In any case, the church broke into two parts, each with one primary bishop. The bishop of Rome had no real rival in the western church. He was the top dog.
About the time of Leo, or a little before that, people in the west quit calling all bishops "Pope," which means "father." They kept using "Pope" for the bishop of Rome, but started using synonyms for other bishops.
Thus it is fair to call Leo the first pope.
There were lots of bishops, but the bishops of the most prosperous and powerful towns were the most powerful. That meant that the bishops of Constantinople, Cairo, and Rome were the top three, a leading triad, a triumvirate, or maybe a father, son, and holy ghost. To the extent that anybody was in charge of the church, it was these three.
Then Cairo was conquered by Rome, and lost all of its importance. So then there were just two bishops that--if they weren't all equal--seemed to outrank the others. Rome and Constantinople were the leading partners and rivals.
Part of why they were rivals was because symbolism doesn't work the same for everybody. In the east, the priests wore beards, and so, to the western priests, they looked like German barbarians. In the west, the priests were clean-shaven and celibate, so, to the priests in the east, they looked like eunuchs.
In any case, the church broke into two parts, each with one primary bishop. The bishop of Rome had no real rival in the western church. He was the top dog.
About the time of Leo, or a little before that, people in the west quit calling all bishops "Pope," which means "father." They kept using "Pope" for the bishop of Rome, but started using synonyms for other bishops.
Thus it is fair to call Leo the first pope.
