On the crucifixion the historical and the confessional accounts still touch. That Jesus was executed by Roman order, on a charge the Gospels frame around the title king of the Jews, is among the most secure facts known about him. Crucifixion was Rome's penalty for sedition and for the low-born, and the early claim of a crucified messiah cut so hard against expectation that its very awkwardness counts, for many historians, as an argument for its historicity.
What follows divides sharply. The Gospels narrate an empty tomb and appearances of the risen Jesus; Paul, writing earlier, hands on a received formula, that Christ died, was buried, was raised, and appeared. Christians confess the resurrection as an act of God vindicating the crucified one, the ground in their telling of everything the faith became. The historian, whose method cannot adjudicate a claim of that order, records instead only what lies open to it: that Jesus' followers came rapidly to believe he had been raised, and that this conviction, more than the execution, is what turned a scattered movement into a mission.
Here the title does its work. Christos, Greek for the Hebrew mashiach, the anointed king, was fastened to him by followers who read his death and their Easter faith as its fulfilment, against a widespread Jewish expectation of a messiah who would triumph rather than die. The confession Jesus is the Christ is the seed of the whole later development, and the exact point at which description must hand over to faith.