Opening ParagraphMlanje is an Administrative District in the Southern Province of Nyasaland. It is densely populated compared with other parts of Central Africa, having a population of 209,522 in 1945, which represented a density of 138 per square mile. The population is tribally heterogeneous, and was composed, in 1945, of 71 per cent. Nguru, 21 per cent. Nyanja, and 5 per cent. Yao people. The Nguru are the most recent arrivals, having immigrated into Nyasaland mainly during the present century. The term Nguru is used to refer to the representatives in Nyasaland of a number of tribes inhabiting that part of Portuguese East Africa which Lies to the east of Nyasaland; these immigrants call themselves Lomwe and in Mlanje are mainly Mihavani and Kokola. The Nyanja are the indigenous inhabitants of the area, who were living there before the invasion of the Mangoche Yao during the nineteenth century. Although they are linguistically distinct, the social organization of these three groups is markedly similar, and there has been a great deal of intermarriage between them, particularly between the Nyanja and the Nguru. No one of them is in sole occupation of a continuous stretch of territory, even the smallest residential groups are often tribally heterogeneous, the similarity of the social organization enabling Nyanja to be absorbed into Nguru hamlets and vice versa. For this reason it is impossible to use a tribal unit as a unit of reference in a discussion of the political organization of this area.