If international relations can be theorised as ‘inter-textual’, as many post-structuralists contend, then why not also – or indeed better – as ‘inter-carbonic’? For, not only is the modern history of carbon to a large degree international. In addition, many of the key historical junctures and defining features of modern international politics are grounded in carbon or, more precisely, in the various socio-ecological practices and processes through which carbon has been exploited and deposited, recycled and mobilised, represented and transformed. This lecture will seek to make this case, arguing that carbon and international relations have been mutually constitutive ever since the dawn of modernity in 1492, and that they will inevitably remain so well into the future, as the global economy’s dependence on fossil carbon continues unabated and the planet inexorably warms. Will climate change generate widespread conflict, or even civilisational collapse? How are contemporary power dynamics shaping responses to climate change? And how, conversely, might decarbonisation transform twenty-first century world order? Building on research in political ecology, the lecture will argue that it is only through a dialectical analysis of ‘inter-carbonic relations’ that we can begin to properly answer these questions. Students of International Relations, it will contend, need to rise to the challenge of climate change by putting the element C at the very centre of their analyses.