The Nuer people are a Nilotic ethnic group concentrated in the Greater Upper Nile region of South Sudan. They also live in the Ethiopian region of Gambella. The Nuer speak the Nuer language, which belongs to the Nilotic language family. They are the second largest ethnic group in South Sudan. The Nuer people are pastoralists who herd cattle for a living. Their cattle serve as companions and define their lifestyle. The Nuer call themselves "Naath" and their language "Thok Naath".

The Nilotic peoples are people indigenous to the Nile Valley who speak Nilotic languages. They inhabit South Sudan, Sudan, Ethiopia, Uganda, Kenya, the eastern border area of Democratic Republic of the Congo, Rwanda, Burundi and Tanzania. Among these are the Burun-speaking peoples, Teso people also known as Iteso or people of Teso, Karo peoples, Luo peoples, Ateker peoples, Kalenjin peoples, Karamojong people also known as the Karamojong or Karimojong, Datooga, Dinka, Nuer, Atwot, Lotuko, and the Maa-speaking peoples.