 Over a period of about eighty years, from 1880, the territory of the present Democratic Republic of Congo became divided into dioceses with their bishops, with apostolic vicariates being the intermediate stage.The evangelization of the Congo began as early as 1484, when Diogo Cam discovered the mouth of the Congo River, known as Zaire until the seventeenth century.Cam's naval chaplain set himself at once to preach to the natives, and won to Christianity the chief of the Sogno, a village on the right bank of the Congo, where he first landed.