Each year, Americans spend over 10 billion dollars on Halloween costumes, candy and decorations. How did a Celtic harvest ritual become one of the most commercial holidays in the world? We will focus on the origins, the global spread and marketing evolution of Halloween. 

      Halloween’s origins date back to the ancient Celtic festival of Samhain. The Celts, a population from over 2000 years ago, living in the area that is now Ireland, the UK and northern France, celebrated their new years on November 1st. The festival of Samahin marked the end of the harvest season and the beginning of winter. The Celts believed that the boundary between the living and the dead blurred on this night. They celebrated around bonfires wearing costumes to ward off spirits. Merging with All Saints’ Day (All Hallows) a Christian feast day on November 1st that honors all saints, giving rise to “All Hallows’ Eve.” 

      Halloween as we know it today truly took shape after the crossing of the Atlantic. In the 19th century, large waves of Irish and Scottish immigrants arrived in North America because many were fleeing the Irish Potato famine between 1845 and 1852. They brought with them their customs from Samhain and All Hallows’ Eve, such as lighting lanterns carved from turnips, dressing up to ward off wandering spirits and telling ghost stories by the fire. In the United States and Canada, these traditions began to blend with other autumn celebrations, including Native American harvest festivals. By the late 1800s, Halloween had evolved into a more community centered event, especially in small towns. People had parades, fall parties and neighborhood gatherings, focussing on games rather than ancient rituals about the dead. 

     By the early 20th century, local leaders wanted to make Halloween more family friendly by removing its dark and mischievous side. This shift helped transform the holiday into a more child focussed celebration. The custom of trick- or- treating emerged in the 1930s and 1950s. After World War II, the candy industry saw an opportunity: with sugar no longer rationed they promoted candy giving as the safe, easy alternative to homemade treats. Cementing “trick or treating” as a Halloween tradition. 

      Mass media then carried Halloween into the global imagination. Radio programs and TV specials in the 1950s and 60s — like It’s the Great Pumpkin, Charlie Brown (1966) — made the holiday feel universal. Later, Hollywood horror films and advertising campaigns turned Halloween into a cultural export, spreading American-style celebrations to places like the UK, France, Japan, and Mexico. What began as a Celtic night of spirits and bonfires had now become a worldwide event of costumes, candy, and creativity. 

       As Halloween became more child-focused, businesses quickly noticed its potential. Candy companies, like Hershey’s and Mars, promoted “trick-or-treating” as a way to sell more sweets, turning an old tradition into a multi-billion-dollar industry. At the same time, the costume market grew, evolving from homemade disguises to mass-produced outfits featuring popular characters from movies, TV, and comic books. Advertising and media further shaped the holiday. TV specials, films, and magazines encouraged decorating homes, hosting parties, and buying themed products. Halloween eventually became a cultural and economic phenomenon, spreading globally through American media and marketing, while still keeping its core of fun, creativity, and community. 

       From its origins as a Celtic festival to a global celebration of costumes, candy, and community, Halloween has undergone a remarkable transformation. What began as a night to honor spirits and the changing seasons has become both a cultural tradition and a commercial phenomenon, shaped by immigrants, communities, and businesses alike. Today, whether through trick-or-treating, parties, or themed media, Halloween continues to bring people together, reminding us that even as customs evolve, the spirit of fun, creativity, and connection remains at its heart. 

History.com Editors. “History of Halloween.” History Channel, 2024. https://www.history.com/topics/halloween/history-of-halloween 

Smithsonian Magazine. “The Origins of Halloween Traditions.” Smithsonian Institution, 2019. https://www.smithsonianmag.com/history/history-halloween-180965240/ 

The Atlantic. “The Candy Industrial Complex That Built Halloween.” The Atlantic, 2019. https://www.theatlantic.com/technology/archive/2019/10/how-candy-companies-built-halloween/600955/ 

BBC News. “How Halloween Became a Billion-Dollar Business.” BBC, 2023. https://www.bbc.com/news/business-67121756 

The Guardian. “How Halloween Conquered the World.” The Guardian, 2021. https://www.theguardian.com/lifeandstyle/2021/oct/30/how-halloween-conquered-the-world 

Time Magazine. “A Brief History of How Halloween Spread Around the World.” TIME, 2020. https://time.com/collection-post/5902324/halloween-around-the-world/