The grandson-in-law of a famous man has both advantages and disadvantages in the task of writing his biography. The relationship to the subject, even if he is dead, affords access to personal details known to few, but family pressures and loyalties may contribute to a shortening of perspective. Marcus Samuel, First Viscount Bearsted, who was variously Britain's first oil magnate, exploiter of international markets, and devoted family man, Lord Mayor of London, military intelligence agent, and respected Jew, has latterly drifted into relative obscurity because the last years of his life were spent away from the ""oil wars"" that gave him his fearless industrial reputation. After his death, a general home and office housecleaning destroyed most of his personal papers, eliminating much of Henriques' advantage of propinquity. It became necessary to do substantial detective work, even in the files of competitors, in order that the book be written at all. That the author came to have a great affection for his topic he attributes as much to the fine character of the man as to the excitement of the times in which he lived. Without duplicating Henriques' researches, it may appear he has given Samuel too peaceful and too honest a nature for one so closely involved in the most vivid economic battle of the century. On the other hand, it is the outcome of that battle, the enduring unity of the British-Dutch amalgamation that resulted in Royal Dutch Shell, that remains as a monument to the lifework of Marcus Samuel, long after the warrior is gone. This is a history of the oil business in quite the same way as it is a biography of one of its pioneers. Its pages may sound like fiction, but they bear the bright stamp of reality.