In the 1860s and 1870s, trance mediums were very popular. Spiritualism generally attracted female adherents, many who had strong interests in social justice. Many trance mediums delivered passionate speeches on abolitionism, temperance, and women's suffrage. Scholars have described Leonora Piper as one of the most famous trance mediums in the history of Spiritualism.
Some scientists of the period who investigated spiritualism also became converts. They included chemist Robert Hare, physicist William Crookes (1832–1919) and evolutionary biologist Alfred Russel Wallace (1823–1913). Nobel laureate Pierre Curie took a very serious scientific interest in the work of medium Eusapia Palladino. Other prominent adherents included journalist and pacifist William T. Stead (1849–1912) and physician and author Arthur Conan Doyle (1859–1930).