This essay begins with an acknowledgment that attempts to understand Brexit are, at this stage, condemned to partial understanding, at best, because as an event it is incomplete and moving in contradictory directions. Just a brief inventory of the many ways in which Brexit can be, and has been, approached gives one a sense of this centrifugalism – sovereignty; globalization; free trade; immigration; racism; disenfranchisement; nostalgia; affect; generational schism; post-imperial decline; neoliberalism; populism; poverty; austerity; class; multiculturalism; cosmopolitanism; far-right and Islamist extremism; Islam and Muslims; refugees; and so on and so on. One particular line of thought emerging among more scholarly treatments from within the arts and humanities (for example, as found in several essays in the volume Brexit and Literature) concerns itself with Brexit as an affective phenomenon, one that speaks to the structures of feeling that bind ‘Britishness’ into a cultural assemblage that goes beyond the artefactual sense of ‘culture’ to that nebulous and barely perceptible ‘way of life’ which constitutes the affective economy of most people living in the British Isles. This, however, is articulated – in the sense used by Stuart Hall – in very different ways depending on class, gender, region, educational background, nationality and, of course, race and ethnicity. This essay will probe the ways in which the affective economy of Brexit is mobilized by picking out one particular thread from within the tangled knot of multiple determinations that have brought the United Kingdom to where it now is: this thread follows the trope of (de)colonization across Brexit rhetorics and places it within a long durée that illuminates the extent to which the affective economy underlying Brexit is deeply embedded in a racialized sense of nationhood that reaches back to the beginnings of Britain’s colonial and thence post-colonial history.