But not all the relief that could come from man, not all the bounties that the prince could bestow, nor all the atonements which could be presented to the gods, availed to relieve Nero from the infamy of being believed to have ordered the conflagration, the fire of Rome. Hence to suppress the rumor, he falsely charged with the guilt, and punished Christians, who were hated for their enormities. Christus, the founder of the name, was put to death by Pontius Pilate, procurator of Judea in the reign of Tiberius: but the pernicious superstition, repressed for a time broke out again, not only through Judea, where the mischief originated, but through the city of Rome also, where all things hideous and shameful from every part of the world find their center and become popular. Accordingly, an arrest was first made of all who pleaded guilty; then, upon their information, an immense multitude was convicted, not so much of the crime of firing the city, as of hatred against mankind.

While some critics desperately try to write this off as a Christian forgery, the evidence is strongly against it.  This passage appears in all versions of Tacitus' writings, even the earliest existing ones.  Also, the tone of this is quite anti-Christian, making it incredibly unlikely to be the work of Christians.  All evidence says that Tacitus wrote this in the early 2nd century.