I've never heard that Eusebius was a master forger. I don't think there's any serious theory that someone forged the writings of Justin, Irenaeus, and Polycarp. There are serious theories that only three of Ignatius' letters are genuine, rather than 7, but I don't believe any mainstream historians are claiming that Eusebius forged all or most of the pre-Nicene writings.
The whole thought's bizarre. Christianity became the main religion of the Roman empire in Eusebius' day. Are you suggesting it had no past?
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