The 1920s, the decade in which The Hairy Ape first appeared, represented an exciting and tumultuous period in American history. It was the age of the flappers (young female socialites intent on dancing and partying), Prohibition, and a massive influx of wealth, often due to stock market speculation. Although the working class saw little change in their quality of life during this period, there was a growing affluent class who could afford to indulge themselves in such leisure activities as a sea cruise to Europe, as Mildred and her aunt do in O'Neill's play.

For many decades up to and beyond the 1920s, as the upper classes were amassing considerable wealth from its advances, the Industrial Revolution was creating a more demanding and intense work environment for both skilled and unskilled laborers. As scientific technology created more powerful means of industry, such as the steam engine...