Pliny the Younger, a roman senator and governor of Bithynia, a Roman province, complained about the number of Christians existing already in 112 A.D, only about 80 years after the crucifixion. Thus there were many witnesses to the truth very early. Speaking of Christianity, Pliny wrote, “For many persons of every age, every rank, and also of both sexes are and will be endangered. For the contagion of this superstition has spread not only to the cities but also to the villages and farms.”
Tacitus was a Roman senator and historian who wrote in 116 A.D. about the persecution of Christians in Rome. He said that the emperor Nero was accused of causing the fire that burned much of the city of Rome in AD 64, and so Nero blamed the fire on Christians and caused them to be persecuted for it. Tacitus mentioned that Christianity originated in Judea and that Christ was executed as a criminal by Pontius Pilate during the reign of Tiberius.
The Jewish historian Flavius Josephus wrote Antiquities of the Jews around 93–94 AD, which includes two references to Jesus and a reference to John the Baptist. Josephus wrote of “the brother of Jesus, who was called Christ, whose name was James”. Josephus was born in 37 A.D., only a few years after Jesus' execution.
Tertullian, an early Christian author, wrote about 200 A.D.: “nearly all the citizens of all the cities are Christians.” “We are of yesterday, and yet we have filled all your places; your cities, islands, villages, townships, assemblies, your very camp, tribes, companies, palace, senate, forum; we leave you only your temples.”
These people were called Christians, as were later believers in Christ. It was recognized that they had the same beliefs, so very early there were large numbers of dedicated people who believed the New Testament accounts of Christ’s life, miracles, death, and resurrection. This was early enough that people would still have known the truth about Christ’s life.