A century and a half ago, extravagant costume balls and skating carnivals were the pinnacle of society’s entertainment, bringing forth a kaleidoscopic array of characters, most drawn from history. The opportunity to reimagine oneself as a noble hero or heroine from the past was no less than the chance of a lifetime. Participants acquired extravagant costumes and flocked to the photographer’s studio, as witnessed by the sheer abundance of mementos of these occasions in the McCord Stewart Museum’s collections. The book accompanies the exhibition Costume Balls: Dressing Up History, 1870-1927 at the McCord Stewart Museum, Montreal. A lead essay presents an overall view of the fancy dress phenomenon, and the major events in Canada with their colonial underpinnings. Other essays look in turn at the commemoration of these balls in art, photography, and publications, a decolonising perspective on the representation of Indigenous and other marginalised peoples in fancy dress, and the ephemeral nature of the extant objects. A section consists of detailed profiles of astounding garments, with several images to show views of each that cannot be seen in the exhibition: interior construction and labels, closeup views of textiles and materials, and comparisons of archival photographs of ball guests in costume. The book is unique amongst historical fashion publications as it is the first to be devoted to fancy dress in such detail.