The Dinka are a group of tribes of south Sudan, inhabiting the swamplands of the Bahr el Ghazal region of the Nile basin, Jonglei and parts of southern Kordufan and Upper Nile regions. They are mainly agro-pastoral people, relying on cattle herding at riverside camps in the dry season and growing millet (Anyanjang) in fixed settlements during the rainy season. They number around 4.5 million people, constituting about 12% of the population of the entire country, and constitute the largest ethnic tribe in South Sudan. Dinka, or as they refer to themselves, Mounyjaang, are one of the branches of the River Lake Nilotes (mainly agro-pastoral peoples of E. Africa who speak Nilotic languages, including the Nuer and Maasai) (Seligman 1965). They are dark African people, differing markedly from the Arabic speaking ethnic groups inhabiting northern Sudan. Dinka are sometimes noted for their height. The popular belief that Dinka "often" reach more than seven feet finds no support in the scientific literature. An anthropometric survey of Dinka men published in 1995 found a mean height of 176.4cm, or roughly 5 ft 9.45 in (Chali 1995). The Dinka have no centralised political authority, instead comprising many independent but interlinked clans. Certain of those clans traditionally provide ritual chiefs, known as the "masters of the fishing spear", who provide leadership for the entire people and appear to be at least in part hereditary.
The Dinka's pastoral lifestyle is also reflected in their religious beliefs and practices (which are animist in character). They have one God, Nhialic, who speaks through spirits that take temporary possession of individuals in order to speak through them. The sacrificing of oxen by the "masters of the fishing spear" is a central component of the Dinka. Age is an important factor in Dinka culture, with young men being inducted into adulthood through an initiation ordeal which includes marking the forehead with a sharp object. Also during this ceremony they acquire a second cow-colour name. Some of the Dinka practice Christianity, a faith introduced to the region by British missionaries in the 19th century.