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".

Halloween is a holiday steeped in history, with roots that trace back to ancient Celtic rituals, Roman customs, and Christian observances. Over the centuries, it has evolved from a spiritual event marking the transition to winter to a festive occasion focused on creativity, community, and fun.

Yet, the Halloween holiday has its roots in the ancient Celtic festival of Samhain (a Gaelic word pronounced “SAH-win”), a pagan religious celebration to welcome the harvest at the end of summer, when people would light bonfires and wear costumes to ward off ghosts.