Political memoirs are not only popular with a general readership, they can also be useful historical source material. The place, form and function of geopolitics within them have been seldom explored, especially in the context of critical geopolitics. This article redresses this balance by arguing that geopolitics is a crucial salient in representations of foreign policy in that it is both a marker of expertise, power and authority, and an effective force majeure , allowing memoirists to depict constraints on action. These conclusions are reached through a theorisation of the form of memoirs in the light of recent innovations in popular geopolitics, in which I propose that they be studied via socio-discursive and fictive categories, in order to discern modes of representation and interactions with audience in justifying and explaining controversial foreign policies. The case study which demonstrates this concerns former UK prime minister Tony Blair's, 2010 memoir, A Journey , a paradigmatic text in terms of how geopolitics functions in the above modes, particularly in his representations of globalisation, the War on Terror and the UK's relationships with the USA and Europe. By bringing together approaches from popular geopolitics and discursive theories of memoirs, I am able to make an original contribution that highlights the importance of political space within one particular and popular literary form and how this is used to justify past foreign policies. [ABSTRACT FROM AUTHOR]