It really comes down to your definition of "Historical Fact".
Jesus is as well, or better attested than many ancient people that no one has any problem accepting as a fact.
Your claim is completely erroneous. You very well know that there is NO archaeological evidence, no artifacts and no pre 70 CE evidence for an HJ.
Richard Carrier an historian argues that Jesus is a figure of mythology.
Jesus is the probably the best attested MYTH character of all myths.
1. Ignatius claimed Jesus was God and born of a Ghost.
2. Aristides attests that Christians claimed Jesus was God from heaven.
3. Justin attests that Christians claimed Jesus was the Son of God born of a Ghost.
4. Irenaeus attests that Christians claimed Jesus was the Son of God and born of a Ghost.,
5. Tertullian attests that Christians claimed Jesus was the Son of God and born of a Ghost.
6. Origen attests that Christians claimed Jesus was God Incarnate born of a Ghost.
7. Hippolytus attests that Christians claimed Jesus was God Creator, the Logos.
8. Eusebius attests that Christians claimed Jesus was the Son of God born of a Ghost.
9. The author of gMatthew claims that Jesus was the Son of God and born of a Ghost.
10. A Pauline writer claimed that Jesus was the Last Adam--a Spirit.
Brainache said:
My favourite example is Pythagoras, look him up: No contemporary accounts. All writings about him are from centuries later and full of mystical religious nonsense.
My favorite is Romulus. Look him up. No contemporary accounts just myth nonsense.
See Plutarch's Romulus.
Romulus was the Son of God and A virgin with a human brother. When he died his body vanished, day was turned into night, then he resurrected, appeared to people and then ascended.
Brainache said:
Yet, no one is campaigning for a "Mythical Pythagoras", even though Historians use exactly the same kinds of analyses to determine the Historical "fact" of his existence.
No-one here is campaigning for an "Historical Romulus".