Oh, friends, there were plenty of eyewitnesses. Luke continues his letters to his friend in Acts.
He documented Jesus’ life after he rose from the dead. Over the next 40 days, Jesus appeared to his disciples and others. Luke spoke to those people who actually saw Jesus alive after he was crucified. Luke also recorded convincing demonstrations, unquestionable evidence, and infallible proofs of the living Christ. (From Acts 1:1-3, AMPC)
And for you doubters, the Jewish historian Flavius Josephus mentioned Jesus twice in his history of Judaism, written in AD 93. He even mentions James, the brother of Christ.
There is no disputing the historical facts that Jesus of Nazareth actually lived. He is mentioned often in Jewish and Roman historians and in dozens of Christian writings.
On the other hand, King Arthur who supposedly lived around AD 500, isn’t even mentioned until several hundred years later
The first Christian records of the life of Christ were written about 25-40 years after he died and rose from the dead. Lots of eyewitnesses still remained to document these writings.
You might not choose to follow Christ, but you can never deny that he lived and died for you.