Here's a fact: of all the major religions in the world with a single founder (which excludes Hinduism, but including Buddhism and Confucianism), it is the only one that its founder did not live to be a revered old man (with the exception of Mohammed, who according to Islam was taken straight to Heaven without experiencing death at all). While the conception/birth and resurrection of Jesus are the stuff of myth, his existence and death are historically real. For me, to votively suffer crucifixion for the sake of his completely beatifical teachings makes him uniquely special. It is those teachings that define 'Christianity'.