Samhain, The Original Halloween.
http://www.aliisaacstoryteller.com

Here is an updated version of a post I wrote around this time last year, explaining the origins of Halloween.

For our ancient ancestors, the day began not with the arrival of dawn, but with the fall of dusk. Therefore, Samhain (pronounced sau-win, and believed to derive from the Old Irish sam, meaning ‘summer’, and fuin, meaning ‘end’) began on the evening of 31st October, and continued until dusk on November 1st. Similarly, their New Year began with the arrival of the dark season, Winter, not halfway through it, as ours does today. Some say this equates with a belief that life is born into the light from the darkness of the womb.