In order to illuminate the physical realities that shaped the conduct of medieval warfare, this chapter traces out the military topography of fortifications, along with their associated infrastructure of roads, ports, and bridges, inherited by medieval Europe from the Roman Empire, and then discusses the multifaceted ways in which medieval polities sought to maintain, expand upon, renew, and ultimately transform this physical infrastructure to suit their needs.

It was not, however, only physical structures that the medieval world inherited from Rome, but also legal and administrative practices, practical engineering handbooks, and even patterns of military thinking. Consequently, we draw attention to the ongoing influence of Roman law and institutions, as well as technological expertise on the organization by medieval governments of the human, material, and financial resources that were necessary to construct and sustain their own military topographies.

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