The genetic history of the British Isles is the subject of research within the larger field of human population genetics. It has developed in parallel with DNA testing technologies capable of identifying genetic similarities and differences between both modern and ancient populations. The conclusions of population genetics regarding the British Isles in turn draw upon and contribute to the larger field of understanding the history of the human occupation of the area, complementing work in linguistics, archaeology, history and genealogy.

Cheddar Man is a human male skeleton found in Gough's Cave in Cheddar Gorge, Somerset, England. The skeletal remains date to around the mid-to-late 9th millennium BC, corresponding to the Mesolithic period, and it appears that he died a violent death. A large crater-like lesion just above the skull's right orbit suggests that the man may have also been suffering from a bone infection.