And secondly, most of the nobles who did go crusading were lords of estates, not their wastrel kids. But more importantly, that analysis ignores religious motivations. We've approached religions as historical phenomena, thinking about how, for instance, the capricious environment of Mesopotamia led to a capricious cadre of Mesopotamian gods. But just as the world shapes religion, religion also shapes the world. And some modern historians might ignore religious motivations, but medieval crusaders sure as hell didn't. I mean, when people came up with that idiom, they clearly thought hell was for sure. To the crusaders, they were taking up arms to protect Christ and his kingdom.