Who was the first head of the Christian Church?

Answer 1

If you mean when all outward expression of faith in Jesus was officially and forcefully standardized that would be the first real pope of the Roman Catholic Church, Leo I, also called Leo the Great. Christianity, or faith in Jesus, is not in itself a religion. Faith is internal. Religion is an OUTWARD expression of faith.

Answer 2

Roman Catholics will, of course, say Peter as they regard him as the first pope in Rome and therefore the Church's first leader.

But actually, things are a little more complex than that because the Church had several leaders in various parts of the world. Thomas, as an example, is believed to have gone to India to be the leader of a Christian Church there and had little or no further dealings with Peter. In a similar way Philip is believed to have gone to Africa and James to Spain.

Another suggestion would be Paul of course as he was both the founder and spiritual leader of the vast majority of churches right across the Mediterranean area from Rome through Greece and Turkey.

What is certain that until the adoption of the Christian faith by the emperor Constantine in the 4th century, when the Bishop of Rome (what we now call 'the pope') became the spiritual leader, there was no real figure who stood out as a single leader of the new religion but several, working in various parts of the world.

Catholic Answer:

In the early days of Christianity communications between the widespread churches were difficult and often nigh onto impossible. As we see in the Acts of the Apostles, other apostles still deferred to Peter when they had questions. Paul, especially, would contact Peter when situations developed that he was not able to answer. There were times that he disagreed with Peter's thinking and they might come to a compromise but he always looked to Peter for leadership and guidance. The lack of communications between Rome and some of the very distant churches eventually led to the Great Schism in 1054. These distant churches in the far east and parts of Africa had been without guidance from Rome for so many years that they evolved their own theology that was, at times, in conflict with Rome's teachings. All came to a head in 1054 when the leaders of the Roman Church and the Eastern Church excommunicated each other.