This is a highly valuable book, which covers a lot of ground and is based on extensive archival research, including German colonial and missionary records. It also draws extensively on oral history - including about 300 interviews with local informants. Preben Kaarsholm, Journal of Africa Becker gives a thorough and balanced analysis... This book is quite an achievement and will be a great resource for both students and academics alike in this field of study. Naasiha Abrahams. Felicitas Becker gives us a balanced understanding of the rise of Islamic radicalism among the Tanzanian Muslim youth Mohamed Bakari, Journal of Islamic Studies a very informative study which sheds light on both the cultural and historical factors that have informed teh spread of Islam in rural and urban locations in the region. Abdullah Sahin, Muslim World Book Review