Book vs. Movie
Though The Grapes of Wrath (1940) is generally a rather true to novel story, there are some changes, some of them fairly significant, that distinguish the two sources.
- The movie contains some censorship of certain aspects of the story for reason of it being a movie which is more restricting than a book
- Steinbeck’s themes of revolt and dislike of America’s socioeconomic system are toned down in the movie
- The ending of the the plot is reversed
- The book portrays the Joads first arriving in the good, functioning government run camp and then moving to a corrupt, bad peach camp. The movie tells this story in the opposite order, most likely to end the movie on a more optimistic and hopeful note for the future.
- Ma Joad ends the movie with her “We’re the people” speech
- This section is from the middle of the novel and is a more uplifting a powerful end to the story than the book’s ending. 
Some overall themes were different in the movie than they were the book. Ford focused the migrants on looking back to a Jeffersonian point of view, with a focus on looking back to a more small farmer narrative of the past. Steinbeck’s novel was more off a call to action with the hope and goal of reform within the migrants and others involved in the depression .
Critiques of the Movie
Some claim that the movie focuses too much on Ma Joad and the focus on the relationship between mother and son . Others claim that Jane Darwell who played Ma Joad did a bad job, she was a weak link in the movie. Darwell’s pick in the movie did have to do with the rush of production, Ford had wanted Beulah Bondi, but this late pick is a main critique of the movie .
The movie was targeted to a larger audience so the Okies were not addressed on their own terms in terms of own culture and individuality. This meant that some of the real issues and other things relating to the migrants we’re toned down from Steinbeck’s nitty gritty novel and John Ford’s own focus was put into the movie instead .