Spirit photography began with William H. Mumler, a Boston jewellery engraver who discovered the effect by pure accident, or so he always claimed, that a self-portrait he developed in 1861 showed a faint second figure he identified as his deceased cousin. Mumler turned the effect into a business, photographing paying clients, most famously a widely circulated image purporting to show the widowed Mary Todd Lincoln with the ghostly figure of her assassinated husband Abraham Lincoln standing behind her, and the practice found an eager, paying market among the bereaved, particularly following the enormous casualties of the American Civil War and, decades later, the First World War, when spirit photography enjoyed a second wave of popularity across Britain and continental Europe.
The trade spread to other named practitioners internationally, including the French photographer Edouard Buguet, who built a substantial Paris and London clientele in the early 1870s producing similarly composed images of deceased loved ones appearing alongside living sitters, charging fees that made the trade a genuinely profitable business rather than a private hobby practiced only among believers.