  Cosmopolitanism slowly began to come to the fore again with the renewed study of more ancient texts, but during the humanist era cosmopolitanism still remained the exception. Despite the fact that ancient cosmopolitan sources were well-known and that many humanists emphasized the essential unity of all religions, they did not develop this idea in cosmopolitan terms. A few authors, however, most notably Erasmus of Rotterdam, explicitly drew on ancient cosmopolitanism to advocate the ideal of a world-wide peace. Emphasizing the unity of humankind over its division into different states and peoples, by arguing that humans are destined by Nature to be sociable and live in harmony, Erasmus pleaded for national and religious tolerance and regarded like-minded people as his compatriots (Querela Pacis).