Woody Guthrie's music was extremely popular during the great depression, especially in California where his fellow "Okie" outsiders would listen to his radio station. His music gave the message that no matter how hard life got, no matter what, you had to keep on fighting for what you believe in. He preached a message of hard work, and that the only way outta this mess was to work for it, and that nobody was going to solve it for them. He had a profound impact on people and also used his radio fame to talk about issues of the time. (politics, politions, lawyers, and businesses.)
Sorry, most of this is based on his online biography. I just read it and wrote this as the result. Good Luck! Stay safe! Don't get Cornoa!