The vitality of present studies on Catholic missions in the colonial and post-colonial worlds 1 owes much to the exploration of unpublished sources While it is now well-known that missionary activity underwent a revival in the 19 th and early 20 th centuries, the opening up of archives and the pursuit of targeted sociological and ethnographic research have contributed to shift the focus to the various mutations of this activity over the course of the long 20 th century Women missionaries were for long overshadowed by their male counterparts, perhaps partly because the men made their archives accessible much sooner and much more widely (Curtis, 2017: 250) Historians and anthropologists of the missions are still dependent on the random release of the private archives of religious congregations, not to mention the Vatican archives, whose declassification does not correspond to any fixed time-schedule The articles in this issue are thus based on sources which have so far been little explored, mainly originating among the female congregations under study (the White Sisters for Algeria, the Montreal Grey Sisters for the Canadian West, the Franciscan Missionary Sisters of Mary for Upper Egypt), but also coming from a local church (Archbishopric of Tunis) and the archives of the papacy of Pius XII (1939)(1940)(1941)(1942)(1943)(1944)(1945)(1946)(1947)(1948)(1949)(1950)(1951)(1952)(1953)(1954)(1955)(1956)(1957)(1958), which were opened in March 2020 and shed new light on missions in times of post-colonial transition and the discussions leading up to the Second Vatican Council 2 While distance in time, and a number of 1 'Post-colonial' is here intended broadly to indicate a period of time following the colonial period, and a context 'freed politically, economically and culturally from colonial forms of domination and their possible successors, but at the same time deeply marked by this domination' (Sibeud, 2004: 87) 2 On the issues and scientific avenues opened by these archives,