The Institute's members are lineal successors to the founding members of the Ethnological Society of London, who in February 1843 formed a breakaway group of the Aborigines' Protection Society, which had been founded in 1837, in the aftermath of the early 19th century Quaker campaign against the African slave trade.

The new society was to be 'a centre and depository for the collection and systematization of all observations made on human races'.

Almost from the start, the membership found itself divided over racialist issues, and between 1863 and 1870 there were two organizations, the Ethnological Society and the Anthropological Society.

The Anthropological Institute of Great Britain and Ireland (1871) was the result of a merger between these two rival bodies.

Permission to add the word 'Royal' was granted in 1907.

The component elements in the Institute's field of interests have established their own professional organization, but the Institute provides a forum for 'anthropology as a whole', embracing social anthropology, biological anthropology and the study of material culture.