Some believe it originates from the Celtic pagan festival of Samhain, meaning Summers End which celebrated the end of harvest season.
If you decide to dress up with your friends this Halloween, then consider getting creative and making your costume instead.
Nicholas Rogers, a historian at York University says that when people prayed for the dead at Hallow Mass, they dressed up. When praying for fertile marriages, the boy choristers in the churches dressed up as virgins. So there was a certain degree of cross dressing in the actual ceremony of All Hallows Eve