- Through the case study of Spanish Lombardy during the Thirty years' war, the Author tries to link the latest results of military history with the politico-institutional framework, with a view to overcome the narrowness of an exclusive military approach. By focussing on the agenda of a commission for the control of the army composed of civil and military authorities from 1638 to 1679 and on the careers of some financiers and military entrepreneurs, the Author suggests the need to abandon the pattern of the militarization of society in order to describe the processes affecting the Milanesado. The military tool appears to be purposefully used to strengthen political and social ties between centre and periphery and also to integrate emerging social, economic and political groups into the Lombard power elite. The interpretation underlying the essay is therefore based on the idea of a «compromise of interests» between centre and periphery of the Spanish imperial system as a way to stabilize the situation of Lombardy.Keywords: Milan, Spanish Monarchy, XVIIth century, power élites, military history, institutional history, Thirty Years' WarParole chiave: Lombardia, Monarchia spagnola, secolo XVII, elites dominanti, storia militare, storia delle istituzioni, Guerra dei Trent'anni