When Maria Isabel Barreno, Maria Teresa Horta, and Maria Velho da Costa, the authors of New Portuguese Letters, were accused of offending public morals and taken to court by the Portuguese dictatorship in 1972, their prosecution gradually became an international cause cèlebre due to the energetic involvement of feminist activists of the so-called second wave, mainly in Western Europe and the United States. Drawing on archival materials held in the Portuguese Ministry of Foreign Affairs and other contemporary sources, this lecture will discuss the highlights of New Portuguese Letters’ unexpected notoriety in the US before and around the 1974 Carnations Revolution, which put an end to the Estado Novo regime.