“The eve of the New Year or Oidhche Shamhna was a gap in time. Thus, the spirits from the Otherworld could enter into our world. Rituals on Oidhche Shamhna include providing hospitality to the dead ancestors. They welcomed the dead with food and drink and left the windows and doors of their homes open for the dead to enter. But all spirits from the Otherworld were not good; there were evil spirits too. To keep evil spirits away from their home, they carved images of spirit-guardians onto turnips and placed them at the doors of their homes. As part of the festivities young people wore strange costumes and moved around the village, pretending to be dead spirits visiting from the Otherworld. The Celts believed that on the eve of New Year not only did the boundary between this world and the Otherworld dissolve, but the structure of society dissolved too. Boys and girls would dress up as members of the opposite sex and play pranks on the elders.”
Witches Of The Craft® 