From the French Revolution onwards, military service became an essential step in the process of constructing masculinity within a militarizing Europe. The military-virile model that developed, including in nations that did not practice conscription, such as the United Kingdom before 1916, was based on subjecting men to physical and mental tests, the brutality of which was supposed to ensure effectiveness. Beginning in the 1860s, changes nevertheless emerged with respect to the training undergone by young men, in an effort to humanize the treatment reserved for soldiers, and to develop their physical and intellectual capacities. This model, which was at the origin of mass armies, was tested from 1914-1920, and generally emerged strengthened from the war years, before being highly praised by authoritarian regimes. In the aftermath of World War Two, there was, if not a rejection, then at least a gradual distancing from this masculine and warlike model on the part of European youth.
Source : Military service and masculinity