Scholars have explored the unique urban history of Algiers, but have largely accepted segregation as fact, focusing on differing visions of French urban planning, debates over social dangers in the shantytowns, or political histories of resistance to colonial rule. There has been little attention paid to how Algiers became a segregated space. Unlike many colonial cities, no formal laws restricted Algerians’ residence, no pass system kept them cordoned to specific zones, no explicit policies empowered landlords to deny tenants based on race. Segregation in Algiers is slippery in the archive, but no less real for its near invisibility. Tracing from colonial conquest in the 19th century to the Algerian War of Independence, I argue that colonial segregation in Algiers was a long-term project of erasure, a shift that began by the French capturing Algiers, defining it as a European city, and constructing Algerians as a people outside of modernity. No one code created segregation in Algiers but rather a slow, constant project of racial violence and expropriation that limited the urban possibilities for Algerians. Still, and despite this history of erasure, the Casbah could also become a chosen home, a space of solidarity and resistance in a colonial city built to reproduce violence.