This book provides an account of the origins, development and character of Islam as a religion, civilisation and form of society, and instrument of power. It covers the spread of Islam from Morocco through sub-Saharan Africa to Afghanistan and from Turkey through inner Asia and Indo-Pakistan to the East Indies over a time period from the sixth century AD until the second half of the twentieth century. It includes a study of the prophet Muhammad, a study of the basic principles of Islam, a survey of the classical age and the Calliphal State and the emergence of Islamic sects and schools of law. The latter part of the book studies globally the 500 years of the middle period of Islamic history and its politics, Islam in modern times, and concludes with a historical profile of Islam in Nigeria from its inception in the eleventh century until the present. The author is a historian at the Univerity of Nigeria and a cultural Christian. The work is based on fact and is essentially historcal in interpretation. It intends to be scholarly in content but manageable for the general reader, and particularly pertinent and informative in the context of Nigeria and existing anxieties between Christianity and Islam.