Most of Of Mice and Men occurs on the Tyler Ranch in California. George and Lennie’s job on the ranch is to help bring in the harvest. The fact that the story takes place during the Great Depression underscores the economic difficulties that George and Lennie face as seasonal workers.
Not all of the story takes place on the ranch, however. As the book opens, George and Lennie have found a nice quiet spot by a river. This is the only time in the novel when things will be this peaceful for them. Steinbeck uses setting to frame the story by having the characters return to this spot at the end of the book, but now things are no longer nice and quiet.
It is also worth noting that Steinbeck divides the ranch setting to show the isolation of the one black character, Crooks. While all the white workers live in the bunkhouse, Crooks is segregated into the barn as the “stable buck.”
The story is set in the Salina's valley of Southern California during the depression (1930s). The main events occur specifically at the river bank, bunk house, and barn. The climax occurs in Chapter 5 when Curly's wife lets Lennie Small stroke her hair and she becomes scared because he is too rough. So Lennie holds her tightly to keep her from screaming and accidently breaks her neck. The resolution occurs when George decides to kill Lennie for his own good by shooting him in the back of the head.
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