Although they are less socially visible than in prior eras, the very rich exist in the US in the mid-20th century. Mills notes that the extremely wealthy are alternately described as robbers or as innovators. However, he seeks to expose the economic and political structure that enabled them to accumulate wealth, and he is less interested in their personal traits. He explains that "institutions always select and form men” (96). In the US, the legality of the corporate form and the right to private property shaped the process of industrialization and enabled a small number of people to accumulate great wealth. Additionally, the state gave free land to railroads and otherwise subsidized corporations. Taking advantage of compliant politicians, the rich used existing laws, broke other laws, and had laws written, all for their own benefit.

Between the Civil War and World War I, men of enormous wealth came into preeminence. To understand them, Mills studies 275 of the richest people living in the US since the Civil War. Specifically, he analyzes the generations that came of age in 1900, 1925, and 1950, and finds that a greater percentage of this group came from the upper class with each generation. In 1900, 39% of the very wealthy emerged from the lower class, while that percentage was 12 in 1925 and only 9 in 1950.