The novel is set in Oklahoma during the time of the drought
in the 1930's. Tom Joad, recently released from the State Penitentiary, is
returning to his father's farm. He is able to hitch a ride for most of the
way. When he reaches a road that is close to where his family lives, the driver
lets him off and he starts to walk the rest of the distance. On the road he
meets Jim Casy who used to preach in Tom's church. Tom invites him to go with
him to see his family and on the way Jim tells him that he no longer is practicing
his profession because he had had a sexual affair with a woman in the congregation.
When they reach the farm, Tom is surprised to find that the farm is deserted.
The novel begins by depicting the misery that was brought on by the drought
that hit the Great Plains in the 1930's. When the drought and dust storms
showed no signs of letting up, many people abandoned their land. Others would
have stayed but were forced out when they lost their land in bank foreclosures.
In all, one-quarter of the population left, packing everything they owned
into their cars and trucks, and headed west toward California.
The misfortunes that the Joad family experience are the result of this natural
disaster. It is through them that Steinbeck describes the historical and social
problems of the common people in the 1930's.