Opening Paragraph The Ibo-speaking people of Eastern Nigeria can be regarded as a single culture area which may provisionally be subdivided into five main divisions: Northern or Onitsha, Southern or Owerri, Western or Ika, Eastern or Cross River, and North-eastern or Abakaliki. The first two divisions, whose boundaries correspond very roughly to those of the Administrative Provinces of Onitsha and Owerri, contain the bulk of the population; the Western occupies the Niger riverain region and the forest country beyond, and their culture has been influenced by that of the Edospeaking tribes farther west, and by Benin; the Cross River Ibo are another marginal group whose affinities with the ‘Semi-Bantu’-speaking tribes on the eastern bank of that river have yet to be studied; while the North-eastern Ibo are a specialized group that has developed, in comparative isolation, a culture and a social structure better adapted to the savannah country in which they live. The remarks which follow refer mainly to the Northern, Southern, and Cross River Ibo; the North-eastern Ibo system differs in many important respects; the Western has not been studied. The terms used in defining Ibo social groupings have been explained in Africa , vol. xix, No. 2, p. 151, and in places where this may cause confusion the ‘official’ or alternative term is given in brackets.