The crossroads -- a place where two roads cross at or about at right angles, otherwise known as "the forks of the road" -- is the subject of religious and folkloric belief all around the world.
In ancient Greece, marker stones commemorating the god Hermes in his priapic form were set at the crossroads. In ancient Rome the similar god Mercury was the crossroads guardian.
In India, the god Bhairava, an older version of great god Siva, is said to guard the crossroads at the outskirts of villages. Stone phalluses and statues of Bhairava's watchful eyes are erected to represent him as a guardian of the boundaries.
In Guatemala, the old Mayan underworld Lord Maam, under his Catholic Saint guise of Maximon or Saint Simon, is generally depicted seated at a crossroads in a chair, just outside a church.
In Africa, almost every cultural group has its own version of the crossroads god. Legba, Ellegua, Elegbara, Eshu, Exu, Nbumba Nzila, and Pomba Gira are African and African-diaspora names (in several languages) for the spirit who opens the way, guards the crossroads, and teaches wisdom.
Some modern anthropologists have given these crossroads gods a new collective name -- trickster gods. In my opinion this is a misnomer, for not all crossroads gods and spirits are tricksters (unreliable, clever, deceitful) and not all trickster gods or spirits are crossroads gods -- the water dwelling kapi of Japan, the shoemakers' elves of Germany, and the wide-ranging Coyote of Native Americas being prime examples of trickster gods and spirits who do not inhabit crossroads.
Because the crossroads is land that belongs to no one, a place outside the borders of town, it is considered a suitable site to perform magical rituals and cast spells. The use of the crossroads as an impromptu altar where offerings are placed and rituals performed is widely encountered in both European and African folklore.
American beliefs about the crossroads are many and they come in numerous variations. There are two major themes regarding crossroads rituals in the African-American hoodoo tradition. While these customs may contain an admixture of European folklore, they are primarily derived from African antecedents.
In hoodoo practice, after one completes a "job of work" or magical ritual, the most neutral way to dispose of remnants such as left-over candle wax, incense ashes, footprint-dirt, or ritual bath water is to carry everything to the crossroads, throw it into the intersection, turn and walk home without looking back. (Alternative methods for the disposal of ritual items include throwing them into running water for get away or moving spells, taking them to a graveyard for hard-core enemy work, or burying them in one's yard for drawing influences toward one.)
If a job such as a Follow Me Boy Spell is worked to link two people, then the trick may be laid at every crossroads between the home of the practitioner and lover's home, that is, each crossroads will be marked with ritual artifacts to cement the bond and draw the desired one closer. Contrariwise, in at least one form of Hot Foot or Drive Away Spell, ritual items are thrown into a series of crossroads leaving town, to push the hated person out of town and to act as guards against his or her return. Also, there is a version of the Crossing Spell in which Graveyard Dirt is buried at a crossroads.
Not all hoodoo rituals take place at an actual crossroads, but when laying tricks or casting magical spells, many practitioners make use of what can be called a "portable crossroads" or circle with a cross inside, known as an "X" or "cross-mark," generally. The cross-mark may br drawn on the ground or on a personal altar with sachet powders or it may be created quite subtly, with a mere five dots rather than with two crossing lines. In the latter case, the dots go at the four points where the crossing lines would touch the circumference of an imagined circle and at the intersection or center-point of the circle. When drawn this way, the pattern is not called a cross-mark but a "five-spot." Although folklorists tend to call the pattern a "quincunx" and some anthropologists use the term "cosmogram," in actual conversations with real practitioners, you will hear them spoken of like this: "You lay down your salt in the four corners and in the center, like the five-spot on dice" or "Sprinkle your powders in the form of a cross-mark inside a circle" or "They'd lay out powders by the door -- a big old X-mark -- to trick you.
A 19th century pen and ink drawing by E. W. Kemble called "The Hoodoo Dance" documents the practice. If you look closely you will see at the center of the dance floor a clearly marked portable crossroads or five-spot: A piece of cloth is laid on the ground and at the four corners of the cloth are set four candle-sticks with burning candles, plus four identical pieces of herbiage -- judging from their size and shape, either four large Clematis flowers or four carefully opened banana (plantain) skins. At the center-point of this portable crossroads is a small bowl heaped full of herbiage, presumably an offering.
The crossroads is the most popular place to perform a specific hoodoo crossroads ritual to learn a skill -- to play a musical instrument, for instance, or to become proficient at throwing dice, dancing, public speaking, or whatever one chooses. As this ritual is usually described, you bring the item you wish to master -- your banjo, guitar, fiddle, deck of cards, or dice -- and wait at the crossroads on three or nine specified nights or mornings. On your successive visits you may witness the mysterious appearances of a series of animals. On your last visit, a "big black man" will arrive. If you are not afraid and do not run away, he will ask to borrow the item you wish to learn. He will show you the proper way to use the item by using it himself. When he returns it to you, you will suddenly have the gift of greatness.
The man who meets people at the crossroads and teaches them skills is sometimes called "the devil" He is also called "the rider," the "li'l ole funny boy" or "the big black man," black in this case meaning the actual colour, not a brown-skinned ("coloured" or Negro) person. Because he shares qualities with and derives from a number of African crossroads spirits (of whom Legba, Ellegua, Elegbara, Eshu, Nbumba Nzila, and Pomba Gira are some African and African-diaspora names), it is a common scholarly conceit to equate the crossroads "devil" with Legba, but that is utterly unheard of in the oral folk tradition.
This African-derived crossroads ritual is one of the most widely distributed beliefs in African-American folklore and is practiced throughout the South. It is the subject of the rest of this essay.
On Supernatural, the episode Crossroad Blues used a variation of this legend, making a deal with the devil, and mentioned Robert Johnson's songs and how he supposedly made a deal with the devil. The Supernatural legend was that, using the hoodoo magic, you could summon the crossroads demon and make a deal with them in exchange for their soul in however many years. There was apparently one main crossroads demon on Supernatural and it was killed by Sam when he shot it with the Colt.