After Jesus's crucifixion, 6 of his 23 apostles, who wore worried the Romans might crucify them too, decided to make peace with the Romans and established the Catholic Church in Rome in modern-day Italy, under the direction of Emperor Caligula. Meanwhile, another 6 out of the 23 apostles, who felt like protesting what happened to him and how the Roman Empire had treated him, established the Protestant Church in protest, in Wittenberg in modern-day Germany, outside areas of Roman control, founding the 6 original Protestant denominations of Lutherans, Calvinists, Anabaptists, Anglicans, Eastern Orthodox, and Unitarians.
The 13th apostle, who we now know as the prophet Mohammed, founded an entirely separate religion, Islam, in Mecca in modern-day Saudi Arabia, likewise outside areas of Roman control. The 14th apostle, a Native American named Moroni, from Palmyra in modern-day upstate New York, founded a Native American branch of Christianity called Mormonism, which died out after a few centuries, but was revived in the 1800s by an archaeologist named Joseph Smith after he unearthed the golden plates Moroni had buried underground. The 8 apostles from 15 thru 22 also all formed 8 rival cults, namely Discordianism, Scientology, the Cult of Cthulhu, Satanism, the Unification Church, Heaven's Gate, the Branch Davidians, and the Peoples Temple. The 23rd apostle, who was then known as Bubba but is nowadays known as J.R. "Bob" Dobbs, founded the Church of the SubGenius in Dallas, Texas in 1953 using Time Control.
Naturally, early Christians didn't want to let people know about any of the 11 rival cults to Christianity, so they left out the stories of most of the apostles, and just stuck with the stories of the 12 most well-behaved apostles (and yes this includes Judas Iscariot, because his selling of information to the Romans for pieces of silver helped pave the way for Emperor Caligula to establish the Roman Catholic Church).
Since its early days, Christianity has hardly changed at all, and modern Christians have almost exactly the same beliefs and practices that the Fightin' Jesus himself originally had. Still, Christianity has helped to give rise to not only the Church of the SubGenius but also all 10 of the rival cults it competes with for members, through the actions of the 11 apostles numbered 13 thru 23. All of this was part of The Fightin' Jesus' original plan, given to him by Jehovah 1, and also given Satan's stamp of approval.