Some fun reading about why we celebrate Halloween a.k.a. All Hollows Eve!
Pope Gregory III designated November 1 as a time to honor all saints and martyrs; the holiday, All Saints’ Day. The evening before was known as All Hallows’ Eve and later Halloween. Over time, Halloween evolved into a secular, community-based event characterized by child-friendly activities such as trick-or-treating. In a number of countries around the world, as the days grow shorter and the nights get colder, people continue to usher in the winter season with gatherings, costumes and sweet treats. In England, saints or holy people are called "hallowed", hence the name "All Hallows’ Day" (All Saints Day 11/1). The evening, before the feast became popularly known as "All Hallows' Eve" or even shorter, "Hallowe'en". Many recipes and traditions have come down for this evening, "All Hallows’ Eve" (now known as Halloween), such as pancakes, boxty bread and boxty pancakes, barmbrack (Irish fruit bread with hidden charms), colcannon(combination of cabbage and boiled potatoes). This was also known as "Nutcrack Night" in England, where the family gathered around the hearth to enjoy cider and nuts and apples. In England "soul cakes" are another traditional food. People would go begging for a "soul cake" and promise to pray for the donor's departed friends and family in exchange for the treat, an early version of today's "Trick or Treat."