Crusaders and Mongols - friends or foes?

In popular Templar literature from time to time publications suggest that there were friendly relationships between the Mongols and the Crusader Christians. Some sources even propose that Jacques de Molay, the last Templar Grand Master was a Mongol warlord. What are the facts?

Christian worship in the 13th and 14th century post-crusade Muslim Holy Land

The expulsion of the Crusaders from the Holy Land in 1291 did not end Arab relations with Western European Christians. Western monks, most notably the Franciscans, continued to live among the Muslims in the Holy Land. The nature of the relations of the Franciscans with the Mamluks serves as an interesting counterpoint to earlier Arab views on the Military Orders.