The earliest mention of Jesus outside the Bible occurs around 55 CE from a historian named Thallos.
There are two passages in the writings of the Jewish historian Josephus, and one from the Roman historian Tacitus, that are generally considered good evidence.
There is only one classical writer who refers positively to Jesus and that is Mara bar Serapion, a Syriac Stoic, who wrote a letter to his son, who was also named Serapion, from a Roman prison. Around 73AD.