A lot of people seem to believe that Halloween is an American import. The pagan festival of Samain (end of harvest) is believed to have been adapted by Christianity in Celtic countries to celebrate All Saints Eve or All Hallow's Eve (een in Scotland/ Ireland). The Eve of All Saints day was when the souls of the dead were believed to roam the earth and dressing up and generally partying was thought to scare them away. It has always been (and still is) popular in these countries and immigrants took this practice over the water. It was not until the early 20thc that it became nationwide in the USA. The British, in recent years have adopted 'trick or treat' and using hollowed out pumpkins instead of turnips (Scots call swedes turnips) My grandchildren go out guising round the neighbours and get sweets, toffee apples, nuts and tablet in return for telling a joke, reciting a poem or singing a song. It is an ancient festival that pre-dates Guy Fawkes although nowadays they both seem more jumbled up together.