This book delivers the first substantial study of the preaching of the Third Crusade (1187-92). It assembles c.200 sermon texts and c.100 manuscripts, to understand the explosive dynamic of mobilization in the Latin West. Dealing with the essential fact that a genre called ‘crusade sermon’ did not exist, it develops methodological devices for identifying sermons relevant for the crusading purpose. The book contests thus the modern historiography, which has placed too much trust in the few chronicle reports. However, its fruitful blending of crusading, preaching, exegesis, manuscript studies, and intellectual history has much to offer beyond crusade studies.