There is, in the deeds of men of action, an interest which is never aroused by those persons of brains and capacity by whom the world is really ruled. The statesman in his cabinet is the god within the machine; it is he who directs the acts of nations, it is he who moves the fleets and armies as if they were pieces on the chess-board; to him, as a rule, is the man of action subordinate, obeying his behests. Rule and governance are his, power both in the abstract and the concrete. Seldom in the history of the world do we come across the men who are at one and the same time statesmen and soldiers, who, taking their destiny in their own hands, work it out to the appointed end thereof. But, as we stray in the by-paths of history, we meet with some who, in their day, have influenced not only the age in which they lived themselves, but also the destinies of generations yet unborn. It would seem incredible that mere pirates, such as the Muslim corsairs of the Mediterranean, could be included in this category, and yet, as their story is unfolded, we shall see how the Sea-wolves rose from the humblest beginnings to trouble the peace of Europe, to found for themselves dynasties which endured.