The Shilluk Kingdom, dominated by the Shilluk people, was located along the left bank of the White Nile in what is now South Sudan and southern Sudan. Its capital and royal residence were in the town of Fashoda. According to Shilluk folk history and neighboring accounts, the kingdom was founded by Nyikang, who probably lived in the second half of the 15th century. A Nilotic people, the Shilluk managed to establish a centralized kingdom that reached its apogee in the late 18th and early 19th centuries, during the decline of the northern Funj Sultanate. In the 19th century, the Shilluk were affected by military assaults from the Ottoman Empire, resulting in the destruction of the kingdom in the early 1860s. The Shilluk king is currently not an independent political leader, but a traditional chieftain within the governments of South Sudan and Sudan. The current Shilluk king is Reth Kwongo Dak Padiet who ascended to the throne in 1993.

The Shilluk is a major Luo Nilotic ethnic group that resides in the northeastern Upper Nile state of South Sudan on both banks of the Nile River in Malakal. Before the Second Sudanese Civil War, the Shilluk also lived in settlements on the northern bank of the Sobat River, close to where the Sobat joins the Nile.