Traditional accounts of the arrival of Saint Patrick and Christianity to Ireland are centered on Meath and its legendary High Kings. Folklore states that he travelled to the kingdom to light a Paschal Fire on the Hill of Slane, in defiance of High-King Lóegaire mac Néill, who was on the nearby Hill of Tara celebrating a pagan festival. Patrick was then summoned to the king's court and so impressed Lóegaire with his teachings that he was allowed to continue preaching Christianity across Ireland. While Christian missionaries were documented in Ireland long before the time of Saint Patrick, and accounts of his activities are heavily shrouded in myth, what is known is that by the late 6th century AD Christianity had supplanted Celtic Paganism in every corner of the island. In a similar manner to how the Celts assimilated prehistoric traditions into their beliefs, many Celtic pagan beliefs and festivities were adapted to Celtic Christianity, such as Samhain, which became Halloween, and Imbolc, which became St. Brigid's Day.