Australian histories of military psychiatry position the First World War as a starting point, due to the unprecedented incidence of shell shock. However, military-medical authorities encountered psychological casualties of war as early as the South African War (1899–1902) and links exist between the wars in terms of official attitudes towards psychiatric disorders. During both conflicts, many physicians believed that ideal Australian masculinity precluded psychological trauma, so emphasised physical diagnosis and treatments, as well as the role of morality in war neurosis. This article positions military psychiatry as an evolving practice, analysing the parallels between the wars with newly uncovered evidence from the South African conflict. These findings necessitate a reconfiguration of the Australian historiography of military psychiatry to include the South African conflict.