Halloween was started by the Celts 2000 years ago. Celts were located in modern day Ireland. They made a bonfire and send a sacrifice to the dead. Some people wore masks to disguise them self from the phantom ghosts. Others just leave treats and hope for the best. Trick or treat has started because people dressed as demons and ghosts and stole the treats people left for the real ghosts. When Irish came to America they made Halloween a special night for millions of kid and adults.