Two Shilluk Collo) men posing for a photo in Malakal, Sudan, now South Sudan circa  1936 (G. Eric and Edith Matson Photograph Collection))

Two Shilluk/Collo men posing for a photo in Malakal, Sudan (now South Sudan) circa 1936 (G. Eric and Edith Matson Photograph Collection/Wikipedia)

The Shilluk are a major Nilotic ethnic group of southern Sudan, living along the western and eastern bank of the Nile around the city of Malakal. They are the third largest majority ethnic group of South Sudan, after the Dinka and their neighbors the Nuer. They are led by a king (reth) considered divine, who traces his lineage back to the culture hero Nyikang, and whose health is believed to affect that of the nation.

The capital of the Shilluk kingdom is Pachodo, near malakal in upper Nile region.

Like most Nilotic groups, cattle-raising formed a large part of the Shilluk economy; however, agriculture and fishing were more significant than usual, and most were sedentary. Most Shilluk have converted to Christianity, while some still follow the traditional religion.

The Shilluk language, belongs to the Luo branch of the Western Nilotic subfamily of Nilo-Saharan.

You can read more about the shilluk people from Wikipedia