When Is Halloween? Halloween, traditionally called “All Hallows' Eve,” is celebrated on the evening before the Christian holy day of All Hallows' Day or All Saints' Day (November 1). Therefore, Halloween is always celebrated on October 31.

The belief that the souls of the dead return home on one night of the year and must be appeased seems to have ancient origins and is found in many cultures. In 19th century Ireland, "candles would be lit and prayers formally offered for the souls of the dead. After this the eating, drinking, and games would begin".

Originally a day to honor the dead, including saints (hallows), martyrs, and all who have passed, Halloween has evolved in popular culture into a celebration of horror and the supernatural. From cat ears and vampire fangs to green face paint, people wear all kinds of costumes to embrace the spooky spirit of the season.

Halloween, a holiday observed on October 31 and noted for its pagan and religious roots and secular traditions. In much of Europe and most of North America, observance of Halloween is largely nonreligious, celebrated with parties, spooky costumes, jack-o'-lanterns, pumpkin carvings, and the giving of candy.