Hill came from a family of distinguished academics – her father, A. V. Hill, had earned a Nobel prize in physiology. Her mother Margaret Keynes was a daughter of the economist John Neville Keynes, and sister of the economist John Maynard Keynes and the surgeon Geoffrey Keynes. Her own brothers were the physiologist David Keynes Hill and the oceanographer Maurice Hill, while her sister Janet married the immunologist John Herbert Humphrey. She graduated with a 2:1 in Economics from Newnham College, Cambridge University in 1933. In 1938 she was a research assistant at the Fabian Society, publishing a book on British unemployment. Hill spent eleven years as a civil servant in London, in the statistics department of the Colonial Office. She lived for a period during the war in Henry Moore's studio. After an interlude in journalism for the weekly West Africa, she spent nearly eleven more years as a Research Fellow/Senior Research Fellow at the University of Ghana between 1954 and 1965. She had an interlude as a Fellow at Cambridge, 1960–61, after which she returned to Ghana and shifted from Economics to the Centre for African Studies as a colleague of Thomas Hodgkin and Ivor Wilks. In 1963, she published her magnum opus, The Migrant Cocoa-Farmers of Southern Ghana, which portrayed and documented the emergence of a class of dynamic indigenous entrepreneurs, who developed as they grew a complex infrastructure that the colonial government could not provide. She left Ghana 1965 as her daughter was at risk from malaria, moving back to Cambridge and became an unpaid research fellow at Clare Hall. She never held a permanent position in the UK. From 1965-73 she did fieldwork in Hausaland in Northern Nigeria supported by small research grants. In 1967, she received a PhD in social anthropology from the University of Cambridge, supervised by Joan Robinson. It was based on her work on migrant cocoa farmers. She was then appointed as fixed-term Smuts Reader in Commonwealth Studies from 1971 to 1979. In 1976-77, dissatisfied with economic anthropology at Cambridge, she lived in Sri Lanka and India and was able to produce a major comparative study with Nigeria. She completed her last fieldwork at the age of 67. Hill published many other influential books, among them the famous Development Economics on Trial. She examined economic aid to developing nations, arguing that aid often went to programmes designed to fit the donor's interests. In her latter years she wrote two books about her family and people of the Fens. She died in her daughter's home in Isleham, Cambridgeshire after suffering for 3 years with senile dementia. Her daughter is Susannah Burn, and Polly had 3 grandchildren, William, Matilda and Florence Burn.
Hill, Polly. 1992. Fante villages in southern Ghana : migration and the 'hopelessness' of food farming. Cambridge : African Studies Centre, University of Cambridge.
Hill, Polly. 1990. The History of the Isleham Fen in the 1930s. privately published.
Hill, Polly and Richard Keynes. 1989. Lydia and Maynard: letters between Lydia Lopokova and John Maynard Keynes. London : Andrâe Deutsch.
Hill, Polly. 1986. Development economics on trial: the anthropological case for a prosecution. Cambridge: Cambridge University Press 0521271029
Hill, Polly. 1986. Talking with Ewe seine fishermen and shallot farmers. Recording and editing by Polly Hill. Cambridge: African Studies Centre, University of Cambridge. Cambridge African monographs v6
Hill, Polly. 1984. Indigenous trade and market places in Ghana 1962-64. material collected and edited by Polly Hill. Jos :Department of History, University of Jos
Hill, Polly. 1982. Dry grain farming families: Hausaland and Karnataka compared. Cambridge: Cambridge University Press
Hill, Polly. 1977. Population, prosperity, and poverty : rural Kano, 1900 and 1970. Cambridge: Cambridge University Press
Hill, Polly. 1972. Rural Hausa: a village and a setting. Cambridge: Cambridge University Press
Hill, Polly. 1970. The occupations of migrants in Ghana. Ann Arbor : University of Michigan. Museum of Anthropology. Anthropological papers, no. 42
Hill, Polly. 1970. Studies in rural capitalism in West Africa. Cambridge : Cambridge University Press
Hill, Polly. 1963. The migrant cocoa-farmers of southern Ghana: a study in rural capitalism. Cambridge : Cambridge University Press
