The Festival of Samhain marks the ending and beginning of the Celtic Year. Samhain (pronounced "Sow-in") comes from the Irish Gaelic and means "Summers End". There is a great deal of distortion as to the true meaning of the Holiday, fostered in large part by religious propaganda perpetuated by overly superstitious fundamentalists.
Sometimes one will hear of an "Evil God" named "Samhain", but such a deity never existed anywhere in Celtic lands or Europe for that matter. It was a literary fiction masquerading as scholarship from the early nineteenth century. Fables of Druids leaving "Jack-o-lanterns" at the homes of families who have helped procure a sacrifice for "Samhain" (or Satan) are likewise scurrilous at best.
Samhain can be viewed a number of ways.
First, it was an important agricultural observance, when the final harvest was taken and the folk were now dependent on stored food, hunting and slaughtering of animals for survival. Herds were culled to eliminate the weak and unnecessary and ensure that the limited amount of food would go around for the next six months. In this aspect, Samhain is a holiday of Plenty and feasting, laying in a layer of fat before the winter, and gathering together for safety and protection.
The harvest being over, the seeds for the next years crops are planted. They'll lie dormant until Oimelc (Feb. 1st) when they will begin to sprout. By Beltain (May 1st) they will have shown growth, and it is this time of year that is concerned with the fertility of the coming crops. Those same crops will be harvested by Samhain, and the cycle begins anew.
In present times the importance of this part of the festival has diminished for most people living in this country, but you should try to see this from the stand- point of a tribal people for whom a bad season meant facing a long winter of famine in which many would not survive to the spring.
(S. McSkimming, Dalriada Heritage Trust )
Samhain is also a time when the veil separating our world, the mortal realm, and the world of the Gods and spirits becomes thin. As such, it is a good time to commune with the recently departed before they continue their journey from death to the "Summerland" - the realm of the Gods. There they can enjoy an eternal paradise of feasting, joy and plenty, until they are ready to cross back over to our realm and become incarnate beings again.
...Death was never very far away, yet to die was not the tragedy it is in modern times. What was of great importance to these people was to die with honour and to live in the memory of the clan and be honoured at the great feast Fleadh nan Mairbh (Feast of the Dead) which took place on Samhain Eve. (S. McSkimming,)
Likewise, the separation between past, present and future becomes blurred, allowing for glimpses not only into the realm of the ever Young, but of things which have not yet come to pass. Divination has been historically popular at Samhain, from the Irish myths; to children casting nuts into a fire and kenning their future sweetheart by the way they pop and burn.
Samhain, as the beginning and ending of the yearly cycle, can be viewed as any other "New Years" celebration.
Sig Lonegren, in a treatise remarks:
So as this Samhain approaches, what is ending in you? What do you have inside that it is time to let go of? No healing is complete until you get beyond recovery. Use Samhain to take the thirteenth step: Transformation. In the Tarot, the thirteenth card of the Major Arcane is Death, and it is ruled by Scorpio. Samhain occurs in Scorpio. The card of Death doesn't necessarily mean physical death (though it can mean that), but more productively, it can be seen as an inevitable heavy change or transformation. Something old must be gotten rid of to make room for something new to be able to come in. Use the magic of this time to say good-bye to an old habit or addiction, an old relationship, or anything else it is time to leave behind.
Samhain is the time when we connect with the vital forces of nature and make ourselves ready for the long descent into winter. It is a time to reflect on that which we've brought into our lives, and that which we need for the times to come. Connecting with our roots and examining the directions we need to grow. We feast with the ancestors and ensure the continuing vitality of our people, be it ourselves, our family or the community in which we dwell.