Halloween costumes are costumes worn on or around Halloween

Halloween costumes are costumes worn on or around Halloween, a festival which falls on October 31. An early reference to wearing costumes at Halloween comes from Scotland in 1585, but they may pre-date this. There are many references to the custom during the 18th and 19th centuries in the Celtic countries of Scotland, Ireland, Mann and Wales Hiiro no Kakera Costumes
. It has been suggested that the custom comes from the Celtic festivals of Samhain and Calan Gaeaf, or from the practise of "souling" during the Christian observance of Allhallowtide. Wearing costumes and mumming has long been associated with festivals at other times of the year, such as on Christmas. Halloween costumes are traditionally based on frightening supernatural or folkloric beings. However, by the 1930s costumes based on characters in mass media such as film, literature, and radio were popular. Halloween costumes have tended to be worn mainly by young people, but since the mid-20th century they have been increasingly worn by adults also.

The wearing of costumes at Halloween may come from the belief that supernatural beings, or the souls of the dead, roamed the earth at this time.

The practice may have originated in a Celtic festival, held on 31 October–1 November, to mark the beginning of winter. It was called Samhain in Ireland, Scotland and the Isle of Man, and Calan Gaeaf in Wales, Cornwall and Brittany. The festival is believed to have pre-Christian roots Cosplay Shop
. After the Christianization of Ireland in the 5th century, some of these customs may have been retained in the Christian observance of All Hallows' Eve in that region—which continued to be called Samhain/Calan Gaeaf—blending the traditions of their ancestors with Christian ones. It was seen as a liminal time, when the spirits or fairies (the Aos Sí), and the souls of the dead, could more easily come into our world. It was believed that the Aos Sí needed to be propitiated to ensure that the people and their livestock survived the winter.

From at least the 16th century, the festival included mumming and guising, which involved people going house-to-house in costume (or in disguise), usually reciting verses or songs in exchange for food. It may have originally been a tradition whereby people impersonated the Aos Sí, or the souls of the dead, and received offerings on their behalf. Impersonating these beings, or wearing a disguise, was also believed to protect oneself from them.[7] It is suggested that the mummers and guisers "personify the old spirits of the winter, who demanded reward in exchange for good fortune".F. Marian McNeill suggests the ancient pagan festival included people wearing masks or costumes to represent the spirits, and that faces were marked (or blackened) with ashes taken from the sacred bonfire. In parts of southern Ireland, a man dressed as a Láir Bhán (white mare) led youths house-to-house reciting verses—some of which had pagan overtones—in exchange for food. If the household donated food it could expect good fortune from the 'Muck Olla'; not doing so would bring misfortune. In 19th century Scotland, youths went house-to-house with masked, painted or blackened faces, often threatening to do mischief if they were not welcomed Kanon Costumes
. In parts of Wales, men went about dressed as fearsome beings called gwrachod, while in some places, young people cross-dressed. Elsewhere in Europe, mumming and costumes were part of other yearly festivals. However, in the Celtic-speaking regions they were "particularly appropriate to a night upon which supernatural beings were said to be abroad and could be imitated or warded off by human wanderers".