groups, the "lui" (freemen) and the "dupi" (serfs). The lui were the chiefs and the fathers of the soil while the lower caste, dupi, were those who had a trade such as iron smelting, ironmonging, or fishing. The dupi were a hereditary class of serfs who had to give their services to the lui. The lui represented the superior cattle owning element of Bari society. Origin Based on Bari folklore, their history dates back to the 15th century when the Bari came from the north. Some places in southern Dinkaland still retain Bari names, which indicate those areas were previously home to the Bari until the Dinka arrived and the Bari fled southwards. The Bari probably arrived in their current location in the 1650s or the early 18th century. Oral history recounts that when they arrived in their present homeland from the north they found a group, the Pari people, there, and drove them away. Slavery Since their arrival in the new land, the Bari have been plagued by war and conflict, especially from slave raiders and Azande. Even before the 19th century, the Arabs and Turks involved in the ivory trade raided slaves from the Bari to supply domestic needs of their home communities and to sell them in the markets of Northern Sudan and beyond. The second expedition to discover the source of the White Nile entered the Bari lands on 24 January 1841. However, with this progress in the quest for knowledge, came undesirable invaders in the form of European and Turkish traders looking for slaves and ivory. This was the first time Bari encountered Europeans travellers. The Bari were lucky in this encounter, as the Turkish army assigned to protect the Nile explorers behaved, unlike the brutality they unleashed on the ethnic groups (Mondari, Dinka, Shilluk) to the north of the Bari, Pojulu, Kakwa to the south and Kuku to the south-east. However, subsequent expeditions were different. The third expedition (1841–42) to discover the source of the White Nile also discovered that ivory was abundant in the Bari area. The rush for ivory tusks in the White Nile valley then escalated. Initially, both European and Arab traders began sponsoring trips to Gondokoro for ivory. And for a decade the Bari freely sold ivory tusks and other artefacts to the traders without intimidation, and no incidents of slavery were reported by that point. In April 1854, the