Halloween began in Ireland in the 5th century BC. 31st October was the end of summer and was as such the Celtic New Year (or Samhain which is now celebrated as a Wiccan sabbat).
It was believed that the souls of the people who had died throughout the year would come back to walk the earth in search of an earthly body which they could possess.
People being scared that they would try to take their bodies dressed up as ghouls and walked the streets so that the spirits would believe they had already been taken and leave them alone.
It is believed that, if possessed by a spirit, the person would be burnt alive to scare other spirits from doing the same thing.
Halloween was introduced into America in the 1840’s.
Trick or treating 
Trick or treating is believed to have originated from medieval times and a custom held on November 2nd (all souls day). Christian children would go from door to door asking for soul cakes. They promised anyone who gave them one that they would say a prayer for their dead relatives.
The children would sing:
A soul cake!
A soul cake!
Have mercy on all Christian souls, for
A soul cake!
Jack O Lanterns 
Stingy Jack was a trickster and a drunk.
On all hallows eve he tricked the devil to climb a tree for some apples and then carved a cross at the bottom. He made a deal that if the devil never tempted him again he would let him down.
When Jack died he was denied access to heaven (for his tricks and drinking) and was denied access to hell (for tricking the devil).
The devil gave jack a single ember placed inside a hollowed out turnip to light his way in limbo.
As part of the Samhain celebrations people would bring home an ember from the communal bonfire and place them in a hollowed out turnip. When the tradition moved to America this was substituted for the pumpkin.
Bobbing for apples 
Bobbing for apples was part of a divination ritual similar in significance to catching the bouquet at a wedding. Young couples would bob for apples and the first person to bite the apple would be the next to marry.
Blowing out the lighted candles 
Another game like bobbing for apples that is linked to relationships and marriage. Seven lighted candles are placed on a table, the blindfolded man or woman is spun around three times and then told to go to the table and blow three times. The number of candles not blown out is the number of years left until marriage. If none are blown out, you will never marry.
Cutting a fortune cake 
The fortune cake is a cake of any size with the following items baked into it:
a button, a coin, a horseshoe, a pebble, a red candy heart, A ring, a tiny key, a tiny round disk of white cardboard and a four-leaf cover or Swastika stick pin.
In the four corners should be placed a wish bone, a swastika, a four leaf clover and a horse shoe and fortune cake should be iced in the middle.
It should be placed at one end of the room and a doll dressed as a witch with a black cat and broom to guard it.
Each guest should go to the table one by one and cut a piece of cake. Once this has been done all of the guests should eat their cake and once everyone has eaten theirs they should share with the group what the fortune cake contained for them.
The items mean the following things:
The one who gets the ring will be married within a year.
The one who gets the button is blessed
The one who gets the key is going on a journey
The one who gets the coin will receive great riches
The one who gets the heart, if whole means a lover; if broken, it means a broken heart.
The one who gets the pebble will have hard times
The one who gets the pin or clover will have success and good luck
The one who gets the blank disk has "no luck at all."
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