Romney’s salient quality is not wealth. It is, for better and worse, his tenacious drive — the sort of relentlessness that we associate with striving immigrants, not rich scions.

Where did this persistence come from? It’s plausible to think that it came from his family history. The philosopher Michael Oakeshott once observed that it takes several generations to make a career. Interests, habits and lore accrue in families and shape those born into them.

The Romney family history, which is nicely described in “The Real Romney” by Michael Kranish and Scott Helman, is a story of tenacious work, setbacks and recovery. People who analyze how Mormonism may have shaped Romney generally look to theology. But the Mormon history, the exodus, matters most.