First published in 1938, C. H. Garrett's The Marian Exiles provides details of almost 800 individuals who left England in the reign of Mary Tudor for fear of religious or political persecution. She has searched through continental archives, particularly in Switzerland and Germany, to produce brief biographies of the known exiles, information which was not readily available to English scholars. A significant minority of the emigrants became important under Elizabeth I, and it is clear that they remained in contact with family and friends in England while abroad. The Protestant views of some of the exiles were radicalised by their experiences in Europe, and some attempts to foster plots against Mary were made. Frankfurt expelled John Knox for seditious preaching against Mary, and the town of Wesel asked its English congregation to leave. While some of Garrett's hypotheses are now outdated, the Census of Exiles remains a valuable resource.