This chapter examines the cultural impact of warfare in a range of contexts. First, the interchange of military technology and ideas is considered, partly in relation to other states emulating Roman practices, but above all in Roman openness to adopting military practices and equipment from their enemies – an important factor in Roman military success. Secondly, the role of the military in disseminating aspects of Roman culture is discussed, including the debate about the term ‘Romanization', the status of Latin in the military forces, soldiers’ use of religious and social rituals, and dietary patterns. Thirdly, the role of written documentation in the military is assessed, alongside the related subject of the extent of literacy among troops, from officers to the rank-and-file.