Between 1960 and 1966, French forces began to prove their nuclear weapon capabilities by conducting seventeen nuclear explosions in the Algerian Sahara. This dissertation pursues an international history of French nuclear ambitions and the resistance and the criticism that they faced at regional, international, and global scales. It does so by tracking radioactive debris from the French explosions—Saharan fallout—and the scientists, activists, diplomats, and other officials who tracked it during the 1960s. This methodology relies on declassified archives—from France, the United States, United Kingdom, Canada, and international organizations—produced for these purposes of nuclear surveillance. Concerns extended beyond the health effects of r...