Crude, cantankerous Grampa Joad is a comical figure in the novel who nevertheless demonstrates the loss of the old way of Midwestern tenant farm life. As Jim Casy observes, Grampa Joad essentially dies the minute he leaves Sallisaw because he was emblematic of their way of life there. Ma often jokingly comments that Grampa isn’t housebroken, that is, civilized. His lack of civility and manners make him seem part of an older, more primal way of being, without artificial civility papered over it. He is a man of the land, a man unafraid of his natural sexual instincts, unprepared to live in a world where agriculture is driven by big business. As comical and crude of a figure as Grampa is, Tom notes that unlike the scared landowners the man from Pampa describes in Chapter 18, Grampa never seemed to fear death when he was alive, even when he was legitimately in danger, because he was truly happy with his life. Grampa’s joy stands in stark contrast to the miserable profit-driven system the Joads face in the present.
However, in crafting Grampa Joad, Steinbeck also romanticizes westward expansion and Manifest Destiny, portraying Grampa Joad “killing the Indians” as a heroic and legitimate way to take land as opposed to the capitalistic California landowners. In the intercalary chapters, it becomes clear that Grampa Joad’s fight against the Native Americans is not an individual trait, but one common to his generation. In other words, he is a stand-in for the archetypal Midwestern settler. Because the novel portrays Grampa Joad as an instinctual man who understands the land, his conquest of the land becomes at worst, inevitable, and at best, heroic. This framework portrays the settlement of the Midwest as a battle of wills between equals as opposed to a systemic process driven by governmental policy.