Mars must be fed. His tools of war demand huge quantities of fodder, fuel, ammunition, and food. All these must be produced, transported, and distributed to contending forces in the field. No one can doubt the importance of feeding Mars in warfare, and it takes no great effort to recognize that logistics has always been a major aspect of large-scale armed struggle. Yet, despite its undeniable importance, surprisingly little has been written about logistics. The literature on warfare is full of the triumphs and tragedies of common soldiers and the brilliance and blundering of generals. But logistics lacks the drama of combat. It can be expressed on balance sheets no more exciting than shopping lists; movement is not measured by the dashing gallop of charging cavalry but by the steady plod of draft horses. Feeding Mars is an important contribution to the study of this essential aspect of warfare as practiced by Western powers from the Middle Ages to the Vietnam War. It deals with logistics across a broader time span than that covered in any other work on the subject and emphasizes the various ways in which the essential materials of war have been produced, acquired, and transported to fighting forces in the field. Feeding Mars makes a major contribution to military history and sheds new light on an important, but too often overlooked, aspect of warfare.