Since the overthrow of President Mursi in mid-2013, Egypt has witnessed an authoritarian rollback and shrinking spaces for civil society. Nationalist discourses have villified popular protest and channelled pressure for reform into a state-centric model of governance. Despite this hostile environment for social mobilization, protest has persisted. Contested Legitimacies explores this resilience of contentious politics through a multimethod approach that is attuned to the physical and discursive interactions among key players in Egypt's protest arena. Drawing from a unique archive of sources, it investigates the rise and fall of different coalitions of contenders, from the Tamarod uprising against Mursi, to the Anti-Coup resistance against the military coup, to the challenges posed by the Tiran and Sanafir island campaign to Al-Sisi's regime. It highlights the decisive impact of battles fought in a discursive arena on the conditions of possibility for street politics: In postrevolutionary Egypt, a contest over the meaning of political legitimacy cemented political polarization, limited social movements' coalition choices, and ultimately paved the way for a restoration of autocracy.