The critical literature on ‘tropicality’– the colonising discourse that constructs the tropical world as the West’s environmental Other – focuses chiefly on its historical links with colonialism and on the agency of Western colonisers. Scant attention has been paid to the trajectory of this discourse between the 1940s and 1970s, or to how it has been resisted by the ‘tropicalised’. This paper teases out how, in this post-war era of decolonisation and Cold War, there arose in Western experience a potent image of the tropics as militant – as combative, belligerent and revolutionary. The term militant tropicality is deployed to recall this image and identify a suite of counter-hegemonic knowledges, practices and experiences emanating from the tropical world that challenged the way the West judged the tropics against the presumed normality of the temperate north. The paper dwells on two sites in the promulgation of this militant tropicality – the Caribbean during the 1940s and 1950s, and Vietnam during the 1960s – and probes some of its salient imaginative and material geographies using a range of sources (literature, art, journalism, revolutionary thought, and government and military records). The paper underscores the (little studied) martial quality of tropicality and how, by the 1960s, militant tropicality had become closely associated with guerrilla wars in jungle settings that fractured the West’s ‘temperate’ model of war.