Outside the Bible
Even people who weren't fans wrote about him.
Two famous historians from the first century mention Jesus. Neither was a Christian, and one of them despised Christians. Here is what they wrote.
He hated Christians and called the movement “a most mischievous superstition.” But he still recorded that “Christus” was executed by Pontius Pilate while Tiberius was emperor.
Tacitus, Annals 15.44He mentions Jesus twice. He calls him “a wise man” and “a doer of wonderful works,” and says Pilate “condemned him to the cross.” Later, writing about something else, he names “the brother of Jesus, who was called Christ, whose name was James.”
Christian copyists later added lines to the first passage, such as “He was the Christ.” Most scholars still think the core, with the works and the cross, is Josephus's own.
Josephus, Antiquities 18.63–64 · 20.200