Decolonization in East Africa was a regional affair that required the remaking of temporal orders. The staggered independence timelines of Tanganyika, Uganda, and Kenya caused considerable consternation due to transnational solidarities and visions for East African Federation. The interminable delays of Kenyan decolonization also threatened the linked economy of the region and diluted the sovereignty of neighboring states. At issue was “liminal sovereignty,” with polities and people languishing between normative legal orders. Against expectations about self-determination, East Africans found themselves in partial control of their collective endeavors. I analyze the tactics of temporal activism by Africans who aimed to undo British control over the pacing, sequencing, and synchronicity of decolonization. The indeterminate geography of decolonization was linked to uncertain temporalities of independence which threatened to subvert self-determination. In East Africa, federation was a style of claims-making and chronopolitics intended to orchestrate the distribution of rights, resources, and authority in a new layering of sovereignty between postcolonies.