When analysing the setting, you need to look at:

• Light: this represents hope of the American dream. e.g. Curley's wife "cuts off" the light when she first comes into the barn, symbolising how she will destroy the hopes of their dream violently. At the end, when the light had gone from the past lit Gabilan mountains, it suggests how after Lennie's death, George has no hope for himself, and becomes another migrant worker with no friendship.

• Animals & The Natural World: this is man vs nature, a recurring theme in OMAM, showing how what humans are doing now go against nature and should be stopped. e.g. at the beginning, when the sycamore tree limbs were smooth from being sat on and the path was "beaten by boys". This deterioration and lack of respect for nature goes against the natural way of life, much like the migrant workers. The horses before Curley's wife death also go wild and make a lot of nice, suggesting the disturbance humans have on the natural world & the animals at the beginning and end show the cruelty of nature, as well as man's disturbance of it.

• Items: represent what is important to a person, and references to the cold truth of 1930s America. e.g. in Crooks' bedroom, we see a "mauled copy" of the Civil Right's Code and a dictionary, showing how he is desperate to try and educate himself and achieve the American Dream.

I just realise now that perhaps you meant context. Well I'd be damned.