Zane Grey 
Day of the Beast 

Though Zane Grey is best remembered as a writer of Westerns, the prolific novelist also tackled social issues in a series of books chronicling World War I. In The Day of the Beast, protagonist Daren Lane returns to the United States after years on the battlefield, only to find that the mood of the country has shifted. This historical novel is as relevant today as it was when it was first published in 1922.