The Irish-English Dictionary published by the Irish Texts Society defines the word as follows:
Samhain, All Hallowtide, the feast of the dead in Pagan and Christian times signalling the close of harvest and the initiation of the winter season, lasting till May, during which troops were quartered. Fairies were imagined as particularly active at this season. From it, the half-year is reckoned. Also called Feile Moingfinne (Snow Goddess).
2 The Scottish Gaelic Dictionary defines it as Hallowtide. The Feast of All Souls. Sam + Fuin = end of summer.
3 Contrary to the information published by many organizations, there is no archaeological or literary evidence to indicate that Samhain was a deity.
Eliade’s Encyclopedia of Religion states as follows:
The Eve and day of Samhain were characterized as a time when the barriers between the human and supernatural worlds were broken… Not a festival honoring any particular Celtic deity, Samhain acknowledged the entire spectrum of nonhuman forces that roamed the earth during that period.
4 The Celtic Gods of the dead were Gwynn ap Nudd for the British and Arawn for the Welsh. The Irish did not have a Lord of Death as such.
Why was the end of summer of significance to the Celts?
The Celts were a pastoral people as opposed to an agricultural people. The end of summer was significant to them because it meant the time of year when the structure of their lives changed radically.
The cattle were brought down from the summer pastures in the hills and the people were gathered into the houses for the long winter nights of story-telling and handicrafts.
What does it have to do with a festival of the dead?
The Celts believed that when people died, they went to a land of eternal youth and happiness called Tír na nOg. They did not have the concept of Heaven and Hell that the Christian Church later brought into the land. The dead were sometimes believed to be dwelling with the Fairy Folk, who lived in the numerous mounds, or sidhe,(pronounced shee or &sh-thee) that dotted the Irish and Scottish countryside. Samhain was the new year to the Celts. In the Celtic belief system, turning points such as the time between one day and the next, the meeting of sea and shore or the turning of one year into the next, were seen as magickal times. The turning of the year was the most potent of these times. This was the time when the veil between the worlds was at its thinnest and the living could communicate with their beloved dead in Tír na nOg.