 Christopher Tyerman (2006) attempted a resolution by arguing for compound causes, presenting the First Crusade as developing out of the Western church reform and theories of holy war as much as being a response to conflicts with the Islamic world throughout Europe and the Middle East.In the view of Jonathan Riley-Smith (2005), additional contingencies such as poor harvests, overpopulation, and a pre-existing movement towards colonizing the frontier areas of Europe have also contributed to the crusade; however, he also takes care to say that "most commentators then and a minority of historians now have maintained that the chief motivation was a genuine idealism".Peter Frankopan (2012) has argued that the First Crusade has been fundamentally distorted by the attention paid by historians to western (Latin) sources, rather than Greek, Syriac, Armenian, Arabic and Hebrew material from the late 11th and 12th centuries.