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".

Samhain was a time when people would honour the deceased and attempt to protect themselves from harmful spirits. To celebrate, they built large bonfires, wore costumes, and performed rituals to ward off malevolent beings.

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.