Jump up ^ "All Hallows Eve Service" (PDF). Duke University. 31 October 2012. Archived (PDF) from the original on 5 October 2013. Retrieved 31 May 2014. About All Hallows Eve: Tonight is the eve of All Saints Day, the festival in the Church that recalls the faith and witness of the men and women who have come before us. The service celebrates our continuing communion with them, and memorializes the recently deceased. The early church followed the Jewish custom that a new day began at sundown; thus, feasts and festivals in the church were observed beginning on the night before.
The practice may have originated in a Celtic festival, held on 31 October–1 November, to mark the beginning of winter. It was called Samhain in Ireland, Scotland and the Isle of Man, and Calan Gaeaf in Wales, Cornwall and Brittany. The festival is believed to have pre-Christian roots. After the Christianization of Ireland in the 5th century, some of these customs may have been retained in the Christian observance of All Hallows' Eve in that region—which continued to be called Samhain/Calan Gaeaf—blending the traditions of their ancestors with Christian ones. It was seen as a liminal time, when the spirits or fairies (the Aos Sí), and the souls of the dead, could more easily come into our world. It was believed that the Aos Sí needed to be propitiated to ensure that the people and their livestock survived the winter.