I rewatch it every couple of years or so...
From wiki...
Critical reception
Steinbeck scholar John Timmerman sums up the book's impact: "The Grapes of Wrath may well be the most thoroughly discussed novel in criticism, reviews, and college classrooms of 20th century American literature."[9] The Grapes of Wrath is referred to as a Great American Novel.[12][13]
At the time of publication, Steinbeck's novel "was a phenomenon on the scale of a national event. It was publicly banned and burned by citizens, it was debated on national talk radio; but above all, it was read."[14] According to The New York Times it was the best-selling book of 1939 and 430,000 copies had been printed by February 1940.[2] In that month it won the National Book Award, favorite fiction book of 1939, voted by members of the American Booksellers Association.[2] Soon it won the Pulitzer Prize for Fiction.[3]
Part of its impact stemmed from its passionate depiction of the plight of the poor, and in fact, many of Steinbeck's contemporaries attacked his social and political views. Bryan Cordyack writes, "Steinbeck was attacked as a propagandist and a socialist from both the left and the right of the political spectrum. The most fervent of these attacks came from the Associated Farmers of California; they were displeased with the book's depiction of California farmers' attitudes and conduct toward the migrants. They denounced the book as a 'pack of lies' and labeled it 'communist propaganda'.[9] Some accused Steinbeck of exaggerating camp conditions to make a political point. Steinbeck had visited the camps well before publication of the novel[15] and argued their inhumane nature destroyed the settlers' spirit.