Early church beliefs varied widely among different Christian groups. All claimed to be rooted in the historical Jesus, but some (such as the Ebionites) emphasized his Jewishness while others (followers of the Greek philosopher Marcion, for example) were anti-Jewish.
The historical Jesus was essentially a Jewish rabbi, teacher, or spiritual leader. This statement is unlikely to sit well with Jews or Christians. But for a long time after Jesus's death, his followers were not necessarily perceived as believers in a religion that was fundamentally different from Judaism.
One of the votes at the Council of Nicaea (A.D. 325) was on the divinity of Jesus. It passed. But it wasn't as close as Leigh Teabing suggests; the vote was 316 to 2. And Christians had generally believed in Christ's divinity since the first century.
Christian book-burnings took place as early as the fourth century. In fact, some bishops made a concerted effort to destroy texts considered heretical.
Pagan mysteries and Christianity show remarkable similarities. Motifs in the story related in the Gospels coincide in many ways with tales told of Osiris in Egypt, Dionysus in Greece and Mithras in Persia.
The church took calculated steps to suppress much of its early history. The question is whether there was a coverup or simply a great historical debate. Conspiracy theorists see the former, and Irenaeus, the second-century bishop of Lyon, wrote a famous work decrying the alternative gospels. But attempts to assess what happened need to recognize diversity of the early church. As Dan Burstein says, "Down one path lay mystics having ecstatic experiences in the desert; down the other lay strong popes, central cathedrals, peasants arranging their lives against the backdrop of heaven and hell, and motivated Christian soldiers prepared to move forward."
Once the church got its act together at the Council of Nicaea, all dissent stopped. The reaction to the Second Vatican Council reforms should be enough to dispose of that assertion.
With the demise of the Gnostic Christians, their teachings survived in underground societies. Despite The Da Vinci Code, the evidence suggests that the Gnostics were rediscovered only through archaeology and references in writers whose works drew more acceptance within the church.
The pagan symbol known as the pentacle was altered by the early church to recast it as evil. Actually, the Christian emperor Constantine used the pentacle as a device. Bonus quibble: Brown says the pentacle represents "the female half of all thingsa concept religious historians call the "sacred feminine" or the "divine goddess." In fact it represents both male and female, like ying and yang.
The French government bowed to pressure from the church and banned Martin Scorsese's movie The Last Temptation of Christ. There were protests but France didn't ban itunlike Chile and Israel (for a while).