The Dinka, largest of Sudan's ethnic groups, were central to early missionary ventures on the Upper Nile, both Roman Catholic and Anglican. Committed to their cattle-based manner of life, however, the Dinka proved among the most resistant of Southern Sudanese peoples, largely indifferent to missionary education and evangelism. Only after Sudanese independence, amidst the upheaval of civil war, did they find reason to embrace Christianity in large numbers. Increasingly Dinka in urban and rural settings adapted Christian faith and teaching to their needs, spiritual, social and political. This thesis seeks to document the history of Christianity among the Dinka both during and after the missionary era. An introductory chapter examines aspects of Dinka anthropology, theories of Nilotic derivation, and speculations as to their earliest religious influences. The problems of missionary translation and variations in Dinka vocabulary are discussed and key Dinka religious terms defined. Chapters II. and III. document Dinka encounters with the soldiers, merchants and missionaries who penetrated their lands during the 19^th Century. Memory of the slave trade and the Mahdiyya, maintained in oral literature, continued to influence Dinka attitudes toward alien religion. Though short lived, the initial Roman Catholic initiatives among the Dinka impacted the thought of Daniel Comboni whose efforts to redeem and educate young slaves led to the conversion of several notable Dinka. Chapters IV. and V. examine 20^th Century Protestant and Roman Catholic mission in Dinkaland.