Catholics, constantine and paganism?

alot of catholicism today is an adaptation of pagan rites and festivals. it's the way many pagans were converted, because the new religion mimicked the old one in so many ways. the pagan festival of Imbolc became Candlemas, Ostara became Easter, Yule became Christmas, Lughnaasadh became Lammas, even Halloween became All Saints Day. i could go on and on. the trinity is also a pagan thing, celtic pagan to be exact. the celts believed three was a sacred number, and in wicca it's evident as the cycle of a woman's life (maiden, mother, crone). when they were converted, the sacred number of three was turned into father, son, holy spirit. and, many of the catholic saints were actually celtic gods and goddesses.