Presbyterian Missions South Sudan
The UPNA opened stations for education and medical work in the south eastern regions of Sudan largely in the sudd, the immense swampland in South Sudan formed by the White Nile and its main eastern tributaries, the Pibor and the Sobat Rivers. The Reformed Church in America asked the UPNA to allow them a share in the work, doubling the American Protestant missionary population in Sudan. Differences in governmental oversight, linguistic and ethnic origins between the Arabic-speaking population of North Sudan and the Nilotic tribes of South Sudan (Anuak, Nuer, Shilluk), together with the greater distances and difficulties in travel, combined with the shared work between the RCA and the UP Sudan Mission to make profound differences in administrative structure. In 1948, the American Presbyterian Mission in Sudan became administratively separated, called the American Mission of the North Sudan and the American Mission of South Sudan. Because so many more mission stations existed in the south, the boarders traveling to Egypt and Schutz always numbered more from the South Sudan than the North Sudan Mission.