Graphic from Mythinglinks.org

Halloween truly is a pagan practice, recognizing that this so-called holiday is actually rooted in the old Celtic festival of Samhain. Although Halloween is commonly celebrated on October 31, the festival of Samhain is a cross-quarter holiday that occurs at the midpoint between the Fall Equinox and the Winter Solstice on November 7.

Astrologically, Samhain (along with the other cross-quarter days of Imbolc, Beltane and Lughnasad) is celebrated at the midpoint of the fixed signs of Taurus, Scorpio, Aquarius and Leo. Fixed signs are the signs of power – like the square, their stability and fixed nature leads to a buildup of energy that opens up a doorway to an explosion of raw power. In Scorpio, that power is directed within, fearlessly exploring the invisible dimensions of life and reaching across dimensions to discover what awaits there.

Samhain was celebrated as the New Year in pre-Christian Celtic lands, and it was thought that during this time the veil between the worlds was at its thinnest. Communication with the dead was widely practiced during Samhain rituals, not surprising because of the association with Scorpio and the underworld of darkness that it rules.

When Christianity attempted to subsume the pagan Celtic festivals into Christian holidays, All Saints or All Hallows Day was established on November 2 with the night before being the Eve of All Hallows which has come down to us as Halloween. Participants still celebrate the souls of the dead during Hallows Eve, but now the creatures from the other side were reviled as evil. Wise women became the evil witches; offerings of food and drink were left out for the dead souls to placate their evil spirits.

Sig Lonegren from Glastonbury writes about Samhain and Scorpio:

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 Arcana 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.

Excellent advice! Magic is afoot, we have only look and the veil between the worlds will part.