The most important of these is the middle section dealing directly with St Francis's encounter with Islam and Sultan al - Malik al Kamil, the ruler of Egypt, Palestine and Syria, during the Fifth Crusade in the early thirteenth century. (faith.org.uk)
The Dominicans, founded by St Dominic (1170 - 1221) in 1215, like the Franciscans, date from the early thirteenth century. (religion-online.org)
His monumental achievement, in such epic works as the Summa Contra Gentiles and the Summa Theologiae, was to marry the wisdom of a millennium of Christian philosophy and theology to the «new philosophy» of Aristotle that had been rediscovered in Europe (largely through the mediation of Arabic philosophers) in the early thirteenth century. (firstthings.com)