Throughout Europe, 30 April is known as Walpurgis nacht and it is the night when ghosts, witches and the spirits of darkness are said to be on the loose.
The night was named after St Walpurga, who is regarded as the protector of humanity against black magic. Walpurga was actually the daughter of the Saxon King Richard who went to Germany over 1,200 years ago. While there she gave her support to the campaign against demonism and her efforts were thought to be so impressive that she was made Abbess of Heidenham. In about the year 777 she was canonized.