Halloween dates back to the ancient Celtic festival of Samhain (pronounced sow-in), which means “Summer’s End”. It marked the end of the summer harvest and the beginning of the long, dark days of winter. 

The Celts celebrated their new year on November 1st. So, on the night of October 31st, they celebrated Samhain.  This is when it was believed the veil between the worlds of the living and the dead was at its thinnest and the ghosts of the dead could return to earth. 

Some believed it was when their loved ones would return to them.  They would leave a seat at the dinner table for them or a treat on their doorstep.  Others believed when the ghosts returned they would cause trouble and damage crops.  Whether they were friendly or destructive, it was believed that just the presence of these spirits made it easier for priests to make predictions about the future. The belief in these prophecies provided comfort to the Celts during the long, dark days of winter. 

During Samhain, the priests would build huge sacred bonfires where people would gather in costumes and offer up sacrifices to burn. The costumes were mostly animal heads and animal skins.  When the celebration was over they would use the flames from the sacred bonfire to re-light their own hearth fires to protect them during the coming winter.

As Christianity spread to Celtic lands, it gradually blended with and replaced older Celtic traditions. Eventually, the church named November 2nd as All Souls’ Day as a day to honor the dead. (Rumor has it this was the church’s attempt to replace the Celtic festival with a church-sanctioned holiday) Similar to Samhain (because it was meant to be its replacement), it was celebrated with big bonfires and costumes. All Saint’s Day was also called “All-hallows” or “All Hallowmas” and the night before it, the traditional night of Samhain in the Celtic religion, began to be called All-Hallows Eve and eventually Halloween.