Halloween originated in Ireland and Scotland, celebrated by Celtic priests called Druids who believed it was the night witches came out. They left food and gifts near homes for the witches. Immigrants brought Halloween to America, where children would dress up and go house to house asking for candy. In recent years, adults have also begun celebrating Halloween by participating in parades dressed as witches and demons and carrying jack-o-lanterns through the streets of New York City late into the night.