Halloween's origins date back to the ancient Celtic festival of Samhain (pronounced sow-in).

The Celts, who lived 2,000 years ago in the area that is now Ireland, the United Kingdom, and northern France, celebrated their new year on November 1. This day marked the end of summer and the harvest and the beginning of the dark, cold winter, a time of year that was often associated with human death. Celts believed that on the night before the new year, the boundary between the worlds of the living and the dead became blurred. On the night of October 31, they celebrated Samhain, when it was believed that the ghosts of the dead returned to earth. In addition to causing trouble and damaging crops, Celts thought that the presence of the otherworldly spirits made it easier for the Druids, or Celtic priests, to make predictions about the future. For a people entirely dependent on the volatile natural world, these prophecies were an important source of comfort and direction during the long, dark winter. (From History.com )

In Norway Halloween celebration is relatively new. I've organized a couple of big local event having a true ball with all the fuzz and the kids. Now I just enjoy the fall foliage and the brightly shining colors before winter blue and grey enters the scene.