When you think about Halloween, do your thoughts turn to watching kids eat a seemingly endless number of treats, playing scary pranks, and families carving giant pumpkins? Today, October 31st brings a day of costumes and trick-or-treating, but why do we celebrate Halloween?

Halloween has a rich history that spans centuries and includes various cultural influences. Its origins can be traced back to an ancient Celtic festival, which marked the end of the harvest season and the onset of winter in Gaelic culture.

Here’s how this now-spooky holiday has changed over time.

Ancient Origins

October 31 was originally called “All Hallows’ Eve” and was later shortened to one word, Halloween. The celebration of Halloween started about 2,000 years ago with the ancient Celtic festival, Samhain, meaning “summer’s end” in Gaelic.

Samhain was the end of harvest, which signified the coming of winter. Initially, the festival was celebrated in Ireland, the United Kingdom, and northern France. The Celtic New Year would begin on November 1. For this reason, they believed the worlds between the living and the dead combined right before the New Year. Celts honored the dead by lighting bonfires, wearing costumes to hide from the bad spirits, and carving gourds to make lanterns.

When the Romans conquered the Celts around 43 AD, they incorporated two of their own festivals into the celebration: Feralia and Pomona.

Feralia, was a day in late October when the Romans commemorated the dead, and Pomona, the goddess of fruits and trees, whose symbol is the apple, which is how apples became associated with Halloween, leading to practices like bobbing for apples.

In the 8th century, Pope Gregory III, in an attempt to get away from pagan rituals, instituted All Hallows Day on November 1 to honor all those who had died. The day before All Hallows Day became All Hallows Eve, later shortened to Halloween.

Halloween spread to the U.S. by Irish immigrants who left Europe during the Potato Famine, which took place from about 1845-1850. The holiday became a time for telling ghost stories and doing pranks. In the 1900s, Halloween wasn’t a day of candy, costumes, and fun, but was rather a day for mischief and bad behavior among kids.

In an attempt to fix this problem, the trend of trick-or-treating was introduced. Families could avoid being tricked and pranked by offering candy to kids; however, trick-or-treating still wasn’t practiced by children across America, and certainly wasn’t nearly as popular as it is today.

Modern Traditions

Trick-or-treating has its roots from when the poor would disguise themselves and go door-to-door asking for food or money in exchange for prayers. This practice was often referred to as “guising” or “souling.” Children adopted the tradition and began dressing up in costumes and singing songs to receive offerings. Throughout the early to mid-1900s, many different gifts were given; however, you can thank Charlie Brown and Donald Duck for the trick-or-treating we know and love today.

In 1951, modern trick-or-treating got a big boost from a Peanuts comic strip — which featured Charlie Brown — and, in 1952, from a Donald Duck animated short. Both the comic and the cartoon gave examples of how proper trick-or-treating should be done. The idea quickly became popular among kids everywhere, with candy quickly becoming the dominant Halloween treat from 1952 onward.

Today’s celebrations often also include costume parties, haunted houses, pumpkin carving, and various community events. Halloween decorations and themes have become widely popular, making it one of the most commercially successful holidays in the U.S.

Different countries celebrate similar festivals that reflect regional beliefs and customs. For example, Mexico celebrates DĂ­a de los Muertos (Day of the Dead) around the same time, which honors deceased loved ones with offerings and festivities.

Halloween has transformed significantly from its ancient origins to a largely commercialized holiday characterized by costumes, candy, and community celebrations. Its mixture of pagan traditions, Roman influences, and Christian adaptations reflects a rich cultural history that continues to evolve today.

So, get out your best costume and a bowl of candy because October 31 is coming up soon!