The book is loosely based on the life of Edward L. Doheny (and the company he co-founded, Pan American Petroleum & Transport Company, the California assets of which became Pan American Western Petroleum Company), and also the strategic alliance Union-Independent Producers Agency, a consortium created in 1910 to bring oil via pipeline from Kern County to the Pacific Coast facilities of Union Oil Company at Port Harford (now called Port San Luis just west of Avila Beach).Numerous parallels exist between the opening setting of the novel, Beach City, and the city of Huntington Beach. Huntington Beach was originally called "Pacific City", for which Beach City is a play off of both names. The novel states that the area had street names like "Telegraph" and "Beach City Blvd". Telegraph Road would be the last street crossed before getting off the highway onto Beach Blvd in the town of Buena Park to travel south to Huntington Beach. James Arnold Ross and Bunny stay in a hotel at the intersection of Beach City Blvd and Coast Drive, similar to Beach Blvd and what would later develop into Pacific Coast Highway, where a hotel and water resort once resided in the early 1900s. In the novel, Beach City is covered in beet and cabbage fields. Huntington Beach historically was covered in beet and celery fields. In the novel, the primary oil field found is on "Prospect Hill". The first confirmed oil wells in Huntington Beach were located on a series of bluffs.The character of Eli Watkins is loosely based on the famous evangelist Aimee McPherson.

Sinclair devoted his writing career to documenting and criticizing the social and economic conditions of the early 20th century in both fiction and nonfiction. He exposed his view of the injustices of capitalism and the overwhelming effects of poverty among the working class. He also edited collections of fiction and nonfiction.