The book of the famous English historian, military and statesman is devoted to the birth and development of the Muslim state in Arabia under Muhammad and the conquest campaigns of the Arabs, as a result of which the Muslim caliphate, often called the "Arab Empire," was created. The book gives a comprehensive look at the history of this truly mighty state. The formation of Muslim society, the formation of the religion and ideology of Islam, the emergence and development of institutions of power, the cultural rise of the Arab world - this is a far incomplete list of topics covered by the English researcher. At the same time, the book, which came out of the pen of Sir John Glabb (1897-1986), is by no means a dry list of scrupulously stated facts. Internal political strife and intrigues, inevitable for a rapidly developing young state, religious clashes between Kharijites and Shiites, the struggle for superiority between representatives of dynasties - all these historical realities of that time acquire the meaning and taste of genuine life on the pages of this work. This impression of a meeting with a great era is also reinforced by the fact that D. Glabb spent thirty-six years in the Middle East, initially being there, as an adviser to the English crown under the Iraqi government, and subsequently he was seconded to the famous Arab Legion, which he headed from 1939 to 1956.