"This book focuses on languages and cultures of one of the world's linguistically most diverse regions, north-eastern Nigeria, and aims at providing new explanations for this outstanding diversity. It explores languages in a context of pervasive multilingualism, explaining their histories and sociocultural backgrounds as super-diverse and constantly changing ones. This is achieved by developing a model which provides new explanations and insights for the linguistic region treated in this book--the convergence zone between the Gongola and Benue valleys of northeastern Nigeria."--Page [4] of cover.